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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No. )

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2023 Proxy Statement and

Notice of Annual General Meeting

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Registered in Ireland—No. 498284

NOTICE OF 2023 ANNUAL GENERAL MEETING OF SHAREHOLDERS SCHEDULED To be held JUNE 29, 2023

To the Shareholders of Alkermes plc:

The 2023 Annual General Meeting of Shareholders (including any adjournments or postponements thereof, the “Annual Meeting”) of Alkermes plc (the “Company” or “Alkermes”), a company incorporated under the laws of Ireland, is scheduled to be held on June 29, 2023 at 2 p.m., Irish Standard Time, at the Company’s offices at Connaught House, 1 Burlington Road, Dublin 4, Ireland, D04 C5Y6, for the following purposes:

Proposal 1 relates solely to the election of seven directors. In addition to the seven director nominees nominated by the Board for election, Sarissa Capital Offshore Master Fund LP (“Sarissa Offshore” and together with its affiliates and associates, “Sarissa”) has provided notice to the Company of its intent to nominate three director nominees for election and such notice has not been withdrawn as of the time of filing of the proxy statement accompanying this notice (the “Time of Filing”). Accordingly, the number of individuals who were, at the Time of Filing, nominated in accordance with the Articles of Association for election or re-election as directors exceeded the number of directors to be elected at the Annual Meeting in accordance with Articles 114 and 149 of our Articles of Association. Therefore, the provisions of Article 151.2 of the Articles of Association that provide for plurality voting (i.e., election of the director nominees receiving the highest number of votes cast “FOR” such nominees) in the event of a contested election will apply with respect to Proposal 1 (and such provisions will apply even if the nomination of any or all of the Sarissa director nominees is withdrawn at or before the Annual Meeting). A separate resolution will be presented at the Annual Meeting for each of the director nominees and, in accordance with the Articles of Association, those seven director nominees receiving the highest number of votes cast in person or by proxy “FOR” their respective resolutions will be elected as the seven directors. “WITHHOLD” votes with respect to any director nominees will have no effect on the election outcome (a “WITHHOLD” is functionally equivalent to an “ABSTAIN” under Irish law).

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Proposals 2 through 5 are ordinary resolutions under Irish law, requiring the affirmative vote of a majority of the votes cast (in person or by proxy) on each resolution at the Annual Meeting for approval. Proposal 6 is a special resolution under Irish law, requiring the affirmative vote of the holders of at least 75% of the votes cast (in person or by proxy) at the Annual Meeting for approval. The foregoing items of business are more fully described in the proxy statement accompanying this notice. Shareholders as of April 17, 2023, the record date for the Annual Meeting, are entitled to notice of and to vote at the Annual Meeting.

During the Annual Meeting, following a review of the Company’s affairs, management will present the Company’s Irish statutory financial statements for the year ended December 31, 2022, and the reports of the directors and the independent auditor and accounting firm thereon. There is no requirement under Irish law that the Irish statutory financial statements be approved by shareholders, and no such approval will be sought at the Annual Meeting.

YOUR VOTE IS VERY IMPORTANT. It is important that your voice be heard and your shares be represented at the Annual Meeting whether or not you are able to attend. We encourage you to cast your vote promptly so that your shares will be represented and voted at the meeting. Any shareholder entitled to attend, speak and vote at the Annual Meeting may appoint one or more proxies, who need not be a shareholder of record of the Company. If you wish to appoint as proxy any person other than the individuals specified on the Company’s proxy card, you may do so by contacting the Company Secretary at Alkermes plc, Connaught House, 1 Burlington Road, Dublin 4, Ireland, D04 C5Y6, Attention: Company Secretary or by delivering to the Company Secretary a proxy card in the form mailed to you or in the form set forth in Section 184 of the Irish Companies Act 2014. Your appointed proxy must attend the Annual Meeting in person in order for your votes to be cast. We recommend that you review the further information on the process for, and deadlines applicable to, voting and appointing a proxy under the section entitled “General Information about the Meeting and Voting” commencing on page 15 of the proxy statement accompanying this notice.

By Order of the Board of Directors.

DAVID J. GAFFIN

Secretary

Dublin, Ireland

May 25, 2023

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR THE ANNUAL MEETING OF SHAREHOLDERS TO BE HELD ON JUNE 29, 2023. This notice, the accompanying proxy statement and the Company’s Annual Report for the year ended December 31, 2022 are available at http://www.proxydocs.com/ALKS. These materials are also available free of charge on the Investors section of our website at www.alkermes.com. Because we have elected to utilize the “full set delivery” option for proxy materials related to the Annual Meeting, we are delivering paper copies of our proxy materials to our shareholders as of the Record Date.

The Company’s Irish statutory financial statements for the year ended December 31, 2022, including the related reports thereon, are available on the Annual Reports page of the Investors section of our website at www.alkermes.com.

If you are a shareholder of record, you may vote by Internet or submit your proxy by telephone prior to the closing of the polls at the Annual Meeting, or, if you elect to vote by mail, your validly executed proxy card must be received by the inspector of elections at the Annual Meeting prior to the closing of the polls at the Annual Meeting. If your ordinary shares are held through a bank, broker or other nominee, please follow the voting instructions and timelines for voting provided by such bank, broker or other nominee in order for your shares to be voted.

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IMPORTANT

Sarissa Offshore has provided notice to the Company of its intent to nominate three director candidates for election to the Board at the Annual Meeting in accordance with the Articles of Association. You may receive proxy solicitation materials from Sarissa. The Company is not responsible for the accuracy of any information contained in any solicitation materials filed or disseminated by or on behalf of Sarissa or any of its representatives or affiliates.

THE BOARD DOES NOT ENDORSE SARISSA’S DIRECTOR NOMINEES. THE BOARD RECOMMENDS THAT YOU VOTE “FOR” THE BOARD’S DIRECTOR NOMINEES ONLY BY USING THE ENCLOSED WHITE PROXY CARD. THE BOARD ALSO RECOMMENDS THAT YOU DISREGARD ANY MATERIALS, AND DO NOT SIGN, RETURN OR VOTE ON ANY BLUE PROXY CARD SENT TO YOU BY OR ON BEHALF OF SARISSA. If you have already voted using a blue proxy card sent to you by Sarissa, you may revoke it by voting using the enclosed WHITE proxy card or through any other means of voting set forth on your proxy card. Only your latest dated, validly executed proxy will count, and any proxy may be revoked at any time prior to its exercise at the Annual Meeting.

Please note that your proxy card looks different this year than in prior years. Because of new regulations of the U.S. Securities and Exchange Commission requiring a “universal proxy card”, the Company’s proxy card is required to list all of Sarissa’s director nominees in addition to the Board’s director nominees. As a result, your proxy card has more director nominee names listed on the proxy card than there are available director positions for election to the Board at the Annual Meeting. Please mark your card carefully. You should vote “FOR” no more than seven director nominees in total. If you vote “FOR” more than seven director nominees, all of your votes on Proposal 1 will be invalid and, depending on the bank, broker or other nominee through which you holder your shares, your votes cast on all other proposals before the Annual Meeting may also be invalid.

THE BOARD RECOMMENDS VOTING “FOR” THE ELECTION OF ALL SEVEN OF THE BOARD’S DIRECTOR NOMINEES UNDER PROPOSAL 1 (AND NOT MARKING A VOTE WITH RESPECT TO ANY OF SARISSA’S NOMINEES UNDER PROPOSAL 1), AND VOTING “FOR” PROPOSALS 2, 3, 4, 5 and 6, USING THE ENCLOSED WHITE PROXY CARD.

If you have questions about how to vote your shares,

please call the firm assisting us with the solicitation of proxies,

Innisfree M&A Incorporated:

Shareholders may call: +1 (877) 750-8334 (toll-free from the U.S. or Canada)

or +1 (412) 232-3651 (from other countries)

Banks and brokers may call collect: +1 (212) 750-5833

ALKERMES PLC  Notice of 2023 Annual Meeting

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Dear Fellow Shareholders,

The 2023 Annual General Meeting of Shareholders (including any adjournments or postponements thereof, the “Annual Meeting”) of Alkermes plc (the “Company” or “Alkermes”), is scheduled to be held on June 29, 2023 at 2 p.m., Irish Standard Time, at the Company’s offices at Connaught House, 1 Burlington Road, Dublin 4, Ireland, D04 C5Y6.

Your vote will be especially important this year because Sarissa Capital Offshore Master Fund LP (“Sarissa Offshore” and, together with its affiliates and associates, “Sarissa”) has provided notice to the Company of its intent to nominate three directors for election to the Company’s Board of Directors (the “Board”) at the Annual Meeting. The Board and Company management have engaged constructively with Sarissa and the Board has considered each of Sarissa’s director nominees. When determining the Board’s recommendations on the nominees and matters before the Annual Meeting, the Board carefully considered the best interests of the Company and all of its shareholders. THE BOARD HAS DETERMINED NOT TO ENDORSE ANY OF SARISSA’S DIRECTOR NOMINEES AND RECOMMENDS THAT YOU VOTE “FOR” THE BOARD’S DIRECTOR NOMINEES ONLY BY USING THE ENCLOSED WHITE PROXY CARD, AND THAT YOU DO NOT MARK ANY VOTE WITH RESPECT TO SARISSA’S DIRECTOR NOMINEES. If you have already signed any blue proxy card provided by or on behalf of Sarissa, you have every legal right to change your vote by completing, signing and dating the enclosed WHITE proxy card and promptly mailing it in the enclosed pre-addressed envelope or following the instructions on the enclosed WHITE proxy card to vote via the Internet or by telephone. If you are a shareholder of record and you choose to submit your proxy by telephone, please call the toll-free number on your WHITE proxy card. If you are a beneficial owner of shares held through a bank, broker or other nominee, please follow the voting instructions provided by your bank, broker or other nominee to determine whether you may submit voting instructions by telephone or by Internet to your bank, broker or other nominee. Only your latest dated, validly executed proxy will count. IT IS EXTREMELY IMPORTANT THAT YOUR SHARES BE REPRESENTED AND VOTED AT THE ANNUAL MEETING.

There are a number of other important proposals for your consideration at the Annual Meeting, including an advisory vote on our executive compensation, ratification of our independent auditors and approval of certain remuneration paid to such auditors, approval of an increase in the number of shares authorized for issuance under our stock option and incentive plan, and renewal of the Board’s Irish share issuance authorities. More information on the Company, the Annual Meeting, and the Board’s recommendations on each matter to be voted on at the Annual Meeting can be found in the enclosed proxy materials or other materials we may send you regarding the Annual Meeting. We encourage you to read these materials carefully when deciding how to vote your shares.

YOUR VOTE IS VERY IMPORTANT. Whether or not you plan to attend the Annual Meeting, we hope you will vote as soon as possible so that your voice is heard.

Thank you for your continued support of Alkermes,

ALKERMES PLC   Letter to Shareholders

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Registered in Ireland—No. 498284

PROXY STATEMENT

2023 ANNUAL GENERAL MEETING OF SHAREHOLDERS SCHEDULED FOR JUNE 29, 2023

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Proxy Summary

This proxy summary highlights information that is described in more detail elsewhere in this proxy statement. This summary does not contain all the information you should consider, and you should read the entire proxy statement carefully before voting. Your vote is very important.

General Information

YOUR VOTE IS VERY IMPORTANT. Your vote is particularly important this year in light of the proxy contest being conducted by a dissident shareholder. We encourage you to vote as soon as possible so that your shares are represented at the meeting. We urge you to vote TODAY by following the instructions on the enclosed WHITE proxy card to vote via the Internet or by telephone or by completing, signing and dating the enclosed WHITE proxy card and promptly mailing it in the enclosed pre-addressed envelope. If you are a shareholder of record and you choose to submit your proxy by telephone, please call the toll-free number on your WHITE proxy card. If you are a beneficial owner of shares held through a bank, broker or other nominee, please follow the voting instructions provided by your bank, broker or other nominee to determine whether you may submit voting instructions by telephone or by Internet to your bank, broker or other nominee. Returning your WHITE proxy card will not prevent you from voting in person at the Annual Meeting but will ensure that your vote is counted if you are unable to attend.

How to Cast Your Vote

If you are a shareholder of record, you have four ways to vote:

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Votes by mail, via the Internet or by telephone must be received by the inspector of elections at the Annual Meeting prior to the closing of the polls at the Annual Meeting.

If your ordinary shares are held through a bank, broker or other nominee, please follow the voting instructions provided by such bank, broker or other nominee in order for your shares to be voted. If you do not give instructions to your broker, your broker will not be able to vote your shares with respect to these proposals. We urge you to instruct your broker, bank or other nominee to vote your shares in accordance with the Board’s recommendations. For more information, see the section entitled “General Information About the Meeting and Voting” beginning on page 15 of this proxy statement.

Purpose of this Proxy Statement

The board of directors of Alkermes plc (the “Board”) is soliciting proxies for use at the 2023 annual general meeting of shareholders of Alkermes plc (including any adjournments or postponements thereof, the “Annual Meeting”). This proxy statement contains important information for you to consider when deciding how to vote on matters to be brought before the Annual Meeting. Please read it carefully. This proxy statement is first being made available to our shareholders on or about May 25, 2023. This proxy statement is also available online at http://www.proxydocs.com/ALKS. The specific proposals to be considered and acted upon at the Annual Meeting are summarized below and described in more detail in this proxy statement.

Index of Frequently Requested Information

Voting Matters and Recommendations of the Board

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Business Overview

Alkermes plc (together with its consolidated subsidiaries, “Alkermes” or the “Company” and referred to herein using terms such as “us” or “we”) is a fully-integrated, global biopharmaceutical company that applies its scientific expertise and proprietary technologies to research, develop, manufacture and commercialize, both with partners and on its own, pharmaceutical products that are designed to address unmet medical needs of patients in major therapeutic areas.

Alkermes has a diversified portfolio of marketed products focused on central nervous system disorders, including proprietary products focused on alcohol dependence, opioid dependence, schizophrenia and bipolar I disorder, and a pipeline of product candidates in development for neurological disorders and cancer. Headquartered in Dublin, Ireland, Alkermes has a research and development (“R&D”) center in Waltham, Massachusetts; an R&D and manufacturing facility in Athlone, Ireland; and a manufacturing facility in Wilmington, Ohio.

In November 2022, as part of an ongoing review of strategic alternatives for the oncology business, we announced our intent to separate our neuroscience and oncology businesses, including a potential separation of the oncology business into an independent publicly-traded company. With the advancement of our lead oncology candidate, nemvaleukin alfa, into potential registration-enabling studies and recent developments in the healthcare industry and regulatory environment, our Board and our leadership believe that separating the oncology business at this time will better enable targeted investment and capital allocation to maximize the potential of each business and that such separation will promote the creation of shareholder value. The separation, if consummated, is expected to be completed in the second half of 2023.

2022 Business Priorities and Highlights

Three strategic priorities guided our management of the business in 2022: commercial execution; advancement of our development pipeline; and a focus on profitability. Underpinning these priorities and the operation of our business is our foundation of strong corporate governance, dedication to patients and to our employees and our commitment to operating in an ethical and responsible manner.

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Consistent with these priorities, 2022 was a year of important accomplishments and new developments for the Company. Highlights included:

Successfully executed our commercial strategy

Significantly progressed our pipeline programs

Continued focus on profitability

Maintained operational excellence

Strengthened our commitment to our people and our stakeholders

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Corporate Governance Highlights

We strive to maintain strong corporate governance practices that promote the long-term interests of the Company and our shareholders and strengthen the oversight of our management and our Board. Highlights of these practices include the following:

Recent Enhancements to our Corporate Governance Policies and Practices

We regularly review and refine our governance policies and practices based on market best practices, shareholder feedback and the evolving needs of our business. In recent years, we took a number of actions to further enhance our corporate governance policies and practices and our Board structure, composition and diversity, which are described below under “Recent Enhancements to Corporate Governance Policies and Practices”.

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Board of Directors – Overview

Our Board is substantially independent, has a strong representation of directors who are diverse in terms of age, self-identified gender and race/ethnicity, and has a mix of newer and longer-tenured directors, providing what we consider to be an appropriate balance of experience, institutional knowledge, fresh perspectives and skillsets. The following graphics reflect the composition of the Board following the Annual Meeting, assuming election of each of the seven Board Nominees.

For additional information about our Board composition, including specific qualifications and experience of, and other information about, the Board Nominees and continuing directors, see the section entitled “Director Diversity, Qualifications and Experience” beginning on page 37 of this proxy statement.

Continued Board Refreshment Highlights

For additional information, see “Board Refreshment and Tenure” on page 55 of this proxy statement.

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Active Shareholder Engagement

Our management team and our Board value, and frequently solicit and respond to, the views of our shareholders. We interact with investors throughout the year and regularly engage with our shareholders through open dialogue and direct communication on a variety of topics, including our business and growth strategy, financial performance, corporate governance, executive compensation practices and environmental, social and governance (“ESG”) matters.

Shareholder Outreach, Engagement and Feedback

For the past several years, we have increased the frequency and scope of our shareholder engagement activities, actively solicited shareholder feedback and, when appropriate and determined by the Board to be in the best interests of the Company and its shareholders, made changes to our governance, compensation and other practices in response to the shareholder feedback received. Our Lead Independent Director and other members of our Board have participated in certain of these shareholder engagements alongside representatives of management. The primary areas of discussion during these engagements have related to:

Board Responsiveness to Shareholder Feedback

Feedback from our shareholder meetings is discussed with management and relayed to the full Board and the relevant committees of the Board, as appropriate. After careful consideration of the feedback received, our Board and management team have taken the following actions in recent years:

2022 Annual Meeting Results and Continued Engagement

At our 2022 Annual Meeting, our proposals received support ranging from approximately 86% to 99% of the votes cast, representing strong shareholder support, and an improvement from our last annual meeting, including for our executive compensation program and our director nominees. Following our 2022 Annual Meeting, we requested engagement meetings with shareholders who collectively held approximately 60% of our outstanding shares and held meetings with shareholders who collectively held approximately 55% of our outstanding shares. Our Lead Independent Director and other members of our Board participated in certain of these meetings alongside representatives of management.

We remain committed to engaging with shareholders and other stakeholders on a regular basis to solicit and consider their views on our business strategy and performance, executive compensation programs and corporate responsibility, sustainability and governance practices.

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Recent Enhancements to Corporate Governance Policies and Practices

Following careful consideration of shareholder feedback, the evolving needs of our business and market trends in governance practices, our Board has taken the following actions in recent years to enhance our corporate governance:  

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We remain committed to corporate governance best practices and regular engagement with our shareholders and other stakeholders to solicit and consider their views on these practices, our executive compensation programs, our corporate responsibility and sustainability initiatives, and our business strategy and performance. We invite shareholders to email us at investor_relations@alkermes.com with any suggestions, comments or inquiries. Shareholder proposals, nominations and other notifications required under the Companies Act or our Articles of Association should not be sent to this e-mail address, but rather should be delivered as set forth in this proxy statement, our Articles of Association and/or the Companies Act, as applicable.

Executive Compensation Highlights

Our executive compensation program is focused on attracting and retaining experienced and well-qualified executive officers who will help advance our critical business objectives, and rewarding them for performance that contributes meaningfully to the creation of shareholder value. Our executive compensation highlights include the following, all of which are designed to align our executives’ incentives with the interests of our shareholders and our corporate objectives:

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Corporate Responsibility, Sustainability and ESG Highlights

Corporate responsibility is inherent in our mission as an organization that actively works to support people living with opioid dependence, alcohol dependence, schizophrenia or bipolar I disorder and tries to help break down barriers that prevent access to care. As we do this important work, we are committed to operating and growing our business in a manner that promotes transparent governance and strong ethics; maintains extensive patient, employee and other stakeholder engagement; and helps us grow our organization strategically, sustainably and responsibly, including with respect to our ESG impacts. The following ESG pillars are deeply integrated into our business, and we continued to formalize our commitment to these pillars with the inclusion of goals related to corporate responsibility in the Company’s 2022 corporate objectives and corresponding 2022 short-term incentive plan:

Our Board actively oversees our corporate responsibility, sustainability and ESG initiatives, including ESG-related risks and opportunities tied to our overall business strategy, and has delegated to each of its standing committees significant oversight responsibilities in respect of such matters. For additional information, see “The Board’s Role in Oversight of Risks and Opportunities” beginning on page 45 of this proxy statement.

Our 2022 ESG highlights

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General Information about the Meeting and Voting

Why am I receiving these proxy materials?

We are making this proxy statement available to you on or about May 25, 2023 on the Internet, and by delivering printed versions to you by mail, because our Board is soliciting your proxy to vote your ordinary shares, $0.01 par value per share, of Alkermes plc (referred to in this proxy statement as “shares” or “ordinary shares”) at the Annual Meeting scheduled to be held on June 29, 2023. This proxy statement contains information about the Company and the items being voted on at the Annual Meeting.

This proxy statement and our Annual Report for the year ended December 31, 2022 (the “Annual Report”) are also available through the Investors section of our website at www.alkermes.com or at http://www.proxydocs.com/ALKS. The information contained on or connected to our website is not incorporated by reference into and should not be considered part of this proxy statement.

Who is soliciting proxies for the Annual Meeting with this proxy statement?

Our Board, on behalf of the Company, is soliciting your proxy to vote your ordinary shares on all matters to be presented at the Annual Meeting, whether or not you attend the Annual Meeting. By completing, signing, dating and returning the enclosed WHITE proxy card or voting instruction form, or by submitting your proxy and voting instructions via the Internet or by telephone, you are authorizing the Company’s named proxy holders to vote your ordinary shares at the Annual Meeting in accordance with your instructions.

Under applicable SEC rules and regulations, members of the Board, director nominees and certain executive officers of the Company are “participants” with respect to the Company’s solicitation of proxies in connection with the Annual Meeting (each such person, a “Participant”). For more information on the Participants in the Company’s solicitation, please see “Additional Information Regarding Participants in the Solicitation” in Appendix C of this proxy statement.

What should I do if I receive a blue proxy card or other proxy materials from Sarissa?

Sarissa Offshore has notified the Company that it intends to nominate three director candidates for election at the Annual Meeting. You may receive proxy solicitation materials and/or calls from Sarissa or its proxy solicitor. The Company is not responsible for the accuracy of any information provided by or relating to Sarissa or its nominees contained in proxy materials filed or disseminated by or on behalf of Sarissa or any other statements that Sarissa may make. Although the Company is required to include all nominees for election on its universal proxy card, for additional information regarding Sarissa’s nominees and any other related information, please refer to Sarissa’s proxy statement, which is accessible without cost at www.sec.gov.

Our Board strongly urges you NOT to sign or return any blue proxy card sent to you by Sarissa. While you may vote for the Board Nominees on either the Company’s WHITE proxy card or Sarissa’s blue proxy card, we strongly encourage you to use the WHITE proxy card to vote your shares, regardless of how you intend to vote.

If you have previously submitted a blue proxy card sent to you by Sarissa, you can revoke it and vote “FOR” the Board Nominees by completing, signing, dating and returning the enclosed WHITE proxy card in the postage-paid envelope provided, or by following the instructions on the WHITE proxy card to vote via the Internet or by telephone. We strongly encourage you to vote via the Internet or by telephone. Only the latest dated, validly executed proxy that you submit will be counted, and any proxy may be revoked at any time prior to its exercise at the Annual Meeting as described below. If you attend and validly vote at the Annual Meeting, your previously submitted proxy card will not be used.

Our Board recommends using the enclosed WHITE proxy card to vote “FOR” each of the seven Board Nominees and that you do not mark a vote with respect to any of the Sarissa Nominees. Our Board recommends that you DISREGARD any blue proxy cards that you may receive from Sarissa or on its behalf.

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What happens if Sarissa withdraws or abandons its solicitation or fails to comply with the universal proxy rules and I already granted proxy authority in favor of Sarissa?

Shareholders are encouraged to submit their votes on the Company’s WHITE proxy card. If Sarissa withdraws or abandons its solicitation or fails to comply with the universal proxy rules after a shareholder has already granted proxy authority to Sarissa or its designees, shareholders can still cast a later-dated vote by mail, telephone or via the Internet using a Company WHITE proxy card. If Sarissa withdraws or abandons its solicitation or fails to comply with the universal proxy rules, any votes that you cast in favor of Sarissa’s nominees will be disregarded and will not be counted for purposes of Proposal 1, regardless of whether such vote is provided on the Company’s WHITE proxy card or on Sarissa’s blue proxy card. Your shares would still be counted for purposes of determining whether a quorum exists, regardless of the invalidity of your votes for purposes of Proposal 1.

What is a universal proxy? Will it be used in connection with the Annual Meeting?

The SEC recently adopted Rule 14a-19 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), commonly referred to as the “universal proxy rules,” requiring the use of a universal proxy card in contested director elections that take place after August 31, 2022. This means that all of the Board Nominees and the Sarissa Nominees will be listed on each proxy card that is sent to shareholders in connection with a contested meeting either by the Company or Sarissa. Shareholders may vote for nominees from either or both of the Board’s Nominees and Sarissa’s Nominees, but in any event shareholders may not validly vote for more nominees than there are available director positions on the Board to be filled. Even though we are required to include the Sarissa Nominees on our WHITE proxy card, it does not mean that we recommend voting for such nominees. The Board recommends that shareholders vote “FOR” the seven Board Nominees, and that shareholders DO NOT MARK A VOTE with respect to any of the Sarissa Nominees.

Because Sarissa has provided notice of its intent to nominate candidates for election to the Board at the Annual Meeting, and such notice has not been withdrawn as of the time that this proxy statement is filed with the SEC, this year’s director elections are considered contested, and a universal proxy card will be used. While you may vote for the Board Nominees on either the Company’s WHITE proxy card or Sarissa’s blue proxy card, we strongly encourage you to use the WHITE proxy card to vote your shares, regardless of how you intend to vote.

What happens if I return a WHITE proxy card but give voting instructions for more than seven candidates under Proposal 1?

If you submit votes “FOR” a greater number of director nominees than there are available director positions for election at the Annual Meeting, then an “over-selection” will have occurred. To the extent an over-selection  occurs on a shareholder’s WHITE proxy card and it is not corrected, all of such shareholder’s votes on Proposal 1 regarding director nominees will be invalid unless timely corrected. If you are a beneficial owner and hold your shares through a bank, broker or other nominee, then depending on the bank, broker or other nominee through which you hold your shares, your votes cast on all other proposals before the Annual Meeting may also be invalid. In the event of an over-selection, your shares will still be counted for purposes of determining whether a quorum exists, regardless of any invalidity of your votes cast on any one or more proposals. We encourage you to vote by Internet or by telephone to avoid an “over-selection.”

What happens if I return a WHITE proxy card but give voting instructions for fewer than seven candidates under Proposal 1?

If you submit votes “FOR” a lesser number of director nominees than there are available director positions for election at the Annual Meeting, then an “under-selection” will have occurred. To the extent an under-selection occurs on any WHITE proxy card that you submit, your shares will only be voted “FOR” those nominees you have so marked and will be voted as a “WITHHOLD” for all other nominees. Withhold votes have no impact on the outcome of Proposal 1, as the voting standard for such proposal is a plurality standard (i.e., the directors who received the highest number of votes “FOR” will be elected). We encourage you to vote by Internet or by telephone to avoid an “under-selection.”

Who can vote at the Annual Meeting?

If you owned ordinary shares of the Company as of the close of trading on the Nasdaq Global Select Market on April 17, 2023 (the “Record Date”), you are entitled to notice of, and to vote at, the Annual Meeting. On the Record Date, there were 166,092,464 ordinary shares issued and outstanding and entitled to be voted.

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Am I a shareholder of record or a beneficial owner?

Shareholders of Record. If, as of the Record Date, your ordinary shares were registered in your name (and not in the name of a bank, broker or other nominee) with the Company’s transfer agent, Computershare Trust Company, N.A., then you are a shareholder of record.

Beneficial Owners. If, as of the Record Date, your ordinary shares were not registered in your name, but rather were held in an account at a bank, brokerage firm or other nominee in the name of your bank, broker, or other nominee, then such shares are held in “street name” and you are the beneficial owner of such shares.

How many votes do I have?

On each matter to be voted upon, you have one vote for each ordinary share you owned as of the Record Date. Cumulative voting is not permitted in the election of directors.

When and where is the Annual Meeting scheduled to be held?

The Annual Meeting is scheduled to be held on June 29, 2023 at 2 p.m., Irish Standard Time, at the Company’s offices at Connaught House, 1 Burlington Road, Dublin 4, Ireland, D04 C5Y6. Admission to the Annual Meeting is restricted to shareholders as of the Record Date and/or their proxy holders.

How do proxies work and how will shares be voted on the WHITE proxy card?

You may choose to designate another person as your ‘proxy’ to vote the shares you own on your behalf. If you designate someone as your proxy in a written document, that document is also called a ‘proxy’ or a ‘proxy card’. Any proxy that is properly executed and received by the Company will be voted in accordance with the instructions provided on the proxy card. Our Board is asking for your proxy to authorize the Company’s named proxy holders to vote your shares at the Annual Meeting in the manner you direct. We encourage you to promptly vote on each of the Company’s proposals to be voted on at the Annual Meeting. If you return a validly executed WHITE proxy card without indicating how your shares should be voted on one or more specific proposals to be voted on at the Annual Meeting and you do not revoke your proxy, your shares will be voted in accordance with the Board’s recommendations set forth in this proxy statement for each proposal for which you did not indicate a vote as follows:

Shares represented by valid proxies received and not subsequently revoked before the Annual Meeting that do not specify instructions on any particular matter to be voted on at the Annual Meeting will be voted at the Annual Meeting in the manner set forth above with respect to such matter. You can revoke your proxy and change your vote as described in the section entitled “Can I change my vote after submitting my proxy?” on page 22 of this proxy statement. If your shares are held through a bank, broker or other nominee, please follow the instructions that you were provided by such bank, broker or other nominee.

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Our Board is not aware of any matters that are expected to come before the Annual Meeting other than those described in this proxy statement. If any other matter is presented at the Annual Meeting upon which a vote may be properly taken, ordinary shares represented by all WHITE proxy cards received by the Company will be voted at the discretion of the named proxy holders as set forth on the enclosed WHITE proxy card.

How do I vote?

It is important that your shares are represented at the Annual Meeting, whether or not you attend the Annual Meeting in person. You may vote “FOR” or may “WITHHOLD” your vote on the election of directors under Proposal 1 (a “WITHHOLD” is functionally equivalent to an “ABSTAIN” under Irish law), and you may vote “FOR” or “AGAINST,” or you may “ABSTAIN” from voting, on each proposal other than Proposal 1 to be voted on at the Annual Meeting.

Shareholders of Record. As a shareholder of record, there are four ways to vote:

If you are a shareholder of record and you choose to submit your proxy by telephone by calling the toll-free number on your WHITE proxy card, your use of that telephone system and in particular the entry of your pin number/other unique identifier, will be deemed to constitute your appointment, in writing and under hand, and for all purposes of the Irish Companies Act 2014, as amended (the “Companies Act”), of Christopher McLaughlin, Carol McNelis, Richie Paul, Thomas Riordan and Scott Winter as your named proxy holders, each with power to act without the other and with full power of substitution, to vote your shares on your behalf in accordance with your telephone instructions.

Beneficial Owners.  If you are a beneficial owner of shares held through a bank, broker or other nominee, please follow the voting instructions provided by your bank, broker or other nominee. In most cases, you may submit voting instructions by telephone or by Internet to your bank, broker or other nominee, or you can sign, date and return a voting instruction form to your bank, broker or other nominee. If you provide specific voting instructions by telephone, by Internet or by mail, your bank, broker or other nominee must vote your shares as you have directed. If you wish to vote in person at the Annual Meeting, you must request and submit a legal proxy from your bank, broker or other nominee.

PLEASE NOTE THAT YOUR PROXY CARD LOOKS DIFFERENT THIS YEAR THAN IN PRIOR YEARS. THIS YEAR, UNDER THE NEW UNIVERSAL PROXY RULES, THE COMPANY’S PROXY CARD IS REQUIRED TO LIST ALL OF THE SARISSA NOMINEES IN ADDITION TO THE BOARD NOMINEES. AS A RESULT, THIS YEAR’S PROXY CARD HAS MORE DIRECTOR NOMINEE NAMES LISTED ON IT THAN THERE ARE AVAILABLE DIRECTOR POSITIONS FOR ELECTION. IN ADDITION, WITH RESPECT TO PROPOSAL 1, YOU MAY ONLY VOTE “FOR” OR “WITHHOLD” YOUR VOTES, WHEREAS WITH RESPECT TO THE OTHER PROPOSALS, YOU MAY VOTE “FOR” OR “AGAINST” OR “ABSTAIN” FROM VOTING. YOU SHOULD VOTE “FOR” NO MORE THAN SEVEN DIRECTOR NOMINEES. PLEASE MARK YOUR PROXY CARD CAREFULLY TO AVOID SELECTING TOO MANY DIRECTOR NOMINEES. IF YOU VOTE “FOR” MORE THAN SEVEN DIRECTOR NOMINEES, ALL OF YOUR VOTES ON PROPOSAL 1 WILL BE INVALID AND, DEPENDING ON THE BANK, BROKER OR OTHER NOMINEE(S) THROUGH WHICH YOU HOLD YOUR SHARES, YOUR VOTES CAST ON OTHER PROPOSALS MAY ALSO BE INVALID. THE BOARD RECOMMENDS THAT YOU VOTE “FOR” THE SEVEN BOARD NOMINEES AND THAT YOU DO NOT MARK A VOTE WITH RESPECT TO ANY OF THE SARISSA NOMINEES. WE ENCOURAGE YOU TO VOTE BY INTERNET OR BY TELEPHONE TO AVOID POTENTIAL CONFUSION OR SELECTING TOO MANY NOMINEES.

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What happens if I do not give specific voting instructions when I deliver my proxy?

Shareholders of Record. If you are a shareholder of record and you:

then the Company’s named proxy holders will vote your shares in the manner recommended by the Board on all matters presented in this proxy statement and such proxy holders may determine in their discretion how to vote your shares in respect of any other matters properly presented for a vote at the Annual Meeting.

Beneficial Owners.  If you are a beneficial owner of shares held in “street name” through a bank, broker or other nominee and you do not instruct your bank, broker or other nominee as to how to vote your shares, your bank, broker or other nominee may still be able to vote your shares in its discretion. Under the rules of the New York Stock Exchange (the “NYSE Rules”), banks, brokers and other securities intermediaries that are subject to the NYSE Rules (as are the vast majority of the banks, brokers and other securities intermediaries who hold shares on behalf of beneficial owners of our shares) ordinarily may use their discretion to vote your “uninstructed” shares with respect to matters considered to be “routine” under the NYSE Rules. However, such banks, brokers or other securities intermediaries may not use their discretion to vote your uninstructed shares with respect to matters considered to be “non-routine” under the NYSE Rules, resulting in such circumstances in what are commonly referred to as “broker non-votes”. We believe that Proposals 1, 2 and 4 are considered “non-routine” matters under the NYSE Rules meaning that your broker may not vote your shares on such proposals in the absence of your voting instructions. We believe that Proposals 3, 5 and 6 are considered to be “routine” matters under NYSE rules, meaning that if you do not return voting instructions to your bank, broker or other nominee by its deadline, your shares may ordinarily be voted by your broker in its discretion on such proposals. However, given that we expect the Annual Meeting to be a contested meeting, if your shares are held in street name and the bank, broker or other nominee holding your shares have provided you with competing proxy materials from Sarissa, under applicable rules, such banks, brokers and other nominees will not be permitted to exercise discretionary authority regarding any of the proposals to be voted on at the Annual Meeting, whether “routine” or not. Accordingly, in such circumstances, if you do not submit any voting instructions to your bank, broker or other nominee, your shares will not be counted in determining the outcome of any of the proposals at the Annual Meeting, nor will your shares be counted for purposes of determining whether a quorum exists. If you receive proxy materials only from Alkermes, your bank, broker or other nominee may vote your shares without your specific instruction with respect to Proposals 3, 5 and 6. If you are a beneficial owner of shares held in street name, in order to ensure your shares are voted, you must provide voting instructions to your bank, broker or other nominee by the deadline provided in the materials you receive from such bank, broker or other nominee. We strongly encourage you to submit your voting instructions as soon as possible and exercise your right to vote as a shareholder.

What is the deadline for voting my shares if I do not vote in person at the Annual Meeting?

If you are a shareholder of record, you may vote by Internet or submit your proxy by telephone prior to the closing of the polls at the Annual Meeting, or, if you elect to vote by mail, your validly executed proxy card must be received by the inspector of elections at the Annual Meeting prior to the closing of the polls at the Annual Meeting.

If you are a shareholder of record and you choose to submit your proxy by telephone, please call the toll-free number on your WHITE proxy card. If you are a beneficial owner of shares held through a bank, broker or other nominee, please follow the voting instructions provided by your bank, broker or other nominee to determine whether you may submit voting instructions by telephone or by Internet to your bank, broker or other nominee.

What does it mean if I receive more than one WHITE proxy card or set of printed proxy materials from the Company?

If your shares are held in more than one account, you will receive more than one WHITE proxy card or voting instruction form. You can, and are urged to, vote all of your shares by completing, signing, dating and returning every WHITE proxy card you receive from the Company. If you choose to vote via the Internet, please vote using the details on each WHITE proxy card you receive to ensure that all of your shares are

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voted. Only your latest dated proxy for each account will count. Please sign each proxy card exactly as your name or names appear on the proxy card. For joint accounts, each owner should sign the proxy card. When signing as an executor, administrator, attorney, trustee, guardian or other representative, please print your full name and title on the proxy card.

If Sarissa proceeds with a solicitation of proxies for the Annual Meeting, the Company expects that it may conduct multiple mailings prior to the Annual Meeting in order to ensure that shareholders have the Company’s latest proxy materials for voting. The Company expects to send you a new WHITE proxy card with each mailing, regardless of whether you have previously voted. We encourage you to vote every WHITE proxy card you receive between now and the time of the Annual Meeting. Only the latest dated, validly executed proxy you submit will be counted, and, if you wish to vote as recommended by our Board, you should only submit WHITE proxy cards.

If you have any questions or need assistance voting, please contact our proxy solicitor, Innisfree M&A Incorporated.

Shareholders may call +1 (877) 750-8334 (toll-free from the U.S. or Canada)

or +1 (412) 232-3651 (from other countries).

Banks and brokers may call collect: +1 (212) 750-5833.

Which ordinary shares are included on a proxy card or voting instruction form?

Each proxy card or voting instruction form represents the ordinary shares in each account that you own as of the close of business on the Record Date. You may receive more than one proxy card or voting instruction form if you hold your shares in multiple accounts, some of your shares are registered directly in your name with the Company’s transfer agent, or some of your shares are held in street name through a bank, broker or other nominee. Please vote the shares on each WHITE proxy card or voting instruction form in order to ensure that all of your shares are counted at the Annual Meeting.

Who is paying for this proxy solicitation?

The Company will pay for the entire cost of soliciting proxies for the Annual Meeting, including expenses relating to the preparation, printing and mailing to shareholders of this proxy statement and other proxy materials. We have retained Innisfree M&A Incorporated to assist us in the solicitation of proxies. We will also reimburse banks, brokers and nominees for their reasonable out-of-pocket costs incurred in connection with forwarding proxy materials to, and soliciting voting instructions from, beneficial owners who hold shares of Alkermes in “street name” in the name of such bank, broker or other nominee. Proxies may also be solicited by our directors and certain of our officers and regular employees, whether in person, by mail, by telephone or by email or other electronic means. Our directors, officers and employees will not be paid any additional compensation for any such solicitation efforts. As a result of the proxy solicitation by Sarissa, the Company will incur additional costs in connection with our solicitation of proxies beyond those that we normally incur for an uncontested annual general meeting of shareholders in which there is not a proxy contest. These costs will be borne by the Company.

What is the quorum requirement?

A quorum of shareholders is necessary to hold a valid Annual Meeting. Under our Articles of Association, a quorum will be present if at least one or more shareholders holding not less than a majority of the issued and outstanding shares entitled to vote at the Annual Meeting are present at the Annual Meeting or represented by proxy. On the Record Date, there were 166,092,464 ordinary shares issued and outstanding and entitled to vote. Thus, the holders of 83,046,233 ordinary shares must be present in person or represented by proxy at the Annual Meeting for a quorum to exist.

Your shares will be counted toward the quorum only if you submit a valid proxy (or one is submitted on your behalf by your bank, broker or other nominee) or if you vote in person at the Annual Meeting. For clarity, this remains true even if your votes cast on one or more proposals are deemed invalid for purposes of such proposal(s). Abstentions, withhold votes and broker non-votes will be counted toward the quorum requirement.

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What vote is required to approve each proposal? How are abstentions and broker non-votes treated?

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How will the Company’s plurality standard for contested director elections affect voting at the Annual Meeting?

At the Company’s extraordinary general meeting of shareholders held on May 13, 2022, our shareholders approved amendments to our Articles of Association that provide for a plurality voting standard for contested director elections. This means that if, at the time the Company files its proxy statement for any general meeting of shareholders, the number of persons who are validly nominated for election as directors exceeds the number of available director positions to be filled at such meeting, then only those director nominees who  receive the highest number of votes will be elected to fill the available director positions. The Company received notice from Sarissa Offshore on February 3, 2023 of its intent to nominate three director candidates for election to the Board at the Annual Meeting. Because Sarissa has not withdrawn its nominations as of the time of the filing of this proxy statement with the SEC, the plurality voting standard will apply with respect to the election of directors at the Annual Meeting.

How will voting on any other business be conducted?

The Board knows of no other matters that will be presented for consideration at the Annual Meeting. However, if any other matters are properly brought before the Annual Meeting, the persons identified as the named proxy holders (or any other person designated as your proxy) are entitled to vote on each such matter in their discretion.

Can I change my vote after submitting my proxy?

Shareholders of Record. If you are a shareholder of record, you may revoke your proxy by taking any of the following actions:

Beneficial Owners.  If you are a beneficial owner, you must contact the bank, broker or other nominee that holds your shares in order to revoke your proxy. If you are a beneficial owner and you wish to vote in person at the Annual Meeting, you must request and submit a legal proxy from your bank, broker or other nominee. While you may vote for the Board Nominees on either the Company’s WHITE proxy card or Sarissa’s blue proxy card, we strongly encourage you to use the WHITE proxy card to vote your shares, regardless of how you intend to vote. If you have previously submitted a proxy card sent to you by Sarissa, you may change your vote by completing and returning the enclosed WHITE proxy card in the postage-paid envelope provided, or by voting via the Internet or by telephone by following the instructions on the WHITE proxy card. Please note that submitting a blue proxy card sent to you by Sarissa will revoke any votes you have previously made via the Company’s WHITE proxy card. Please be aware that marking “WITHHOLD” with respect to any of the Sarissa Nominees on a blue proxy card sent to you by Sarissa is not the same as voting “FOR” the Board Nominees because even marking “WITHHOLD” with respect to the Sarissa Nominees on a Sarissa proxy card will revoke any WHITE proxy card you may have previously submitted. Whether or not you plan to attend the Annual Meeting, we urge you to sign, date and return the enclosed WHITE proxy card in the postage-paid envelope provided, or vote via the Internet or by telephone as instructed on the WHITE proxy card TODAY. If you are a shareholder of record and you choose to submit your proxy by telephone, please call the toll-free number on your WHITE proxy card. If you are a beneficial owner of shares held through a bank, broker or other nominee, please follow the voting

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instructions provided by your bank, broker or other nominee to determine whether you may submit voting instructions by telephone or by Internet to your bank, broker or other nominee.

Who will count the votes and how are votes counted?

The Board has appointed, and we have retained, First Coast Results, Inc. to serve as the independent inspector of elections for the Annual Meeting. For Proposal 1, the inspector of elections will separately count votes “FOR” and “WITHHOLD” votes; however, “WITHHOLD” votes have no effect on the outcome of Proposal 1. For each other proposal to be voted on at the Annual Meeting, the inspector of elections will separately count votes “FOR,” “AGAINST,” abstentions and, if applicable, broker non-votes.

What do I need for admission to the Annual Meeting?

All shareholders attending the Annual Meeting in person will be required to show valid government-issued picture identification. If your ordinary shares are held in street name by a bank, broker or other nominee, you will also need to bring evidence of your ordinary share ownership as of the Record Date, such as your most recent brokerage account statement or a copy of your voting instruction form. If you do not have valid picture identification and, if applicable, proof of your share ownership, you may not be admitted to the meeting.

Do shareholders have any appraisal or dissenters’ rights on the matters to be voted on at the Annual Meeting?

No, shareholders of the Company will not have rights of appraisal or dissenters’ rights with respect to any matter identified in this proxy statement to be acted upon at the Annual Meeting.

How can I find out the results of the voting at the Annual Meeting?

We plan to report final voting results in a Current Report on Form 8‑K (“Form 8-K”) to be filed with the SEC within four business days after the conclusion of the Annual Meeting. If final voting results are not available to us in time to file a Form 8‑K within four business days after the Annual Meeting, we intend to file a Form 8‑K to publish preliminary results and, within four business days after the final results are known to us, file an additional Form 8‑K to report the final results. You will be able to find a copy of these Form 8‑Ks on the Internet electronic data system of the SEC, referred to as EDGAR, available at www.sec.gov or through the Investors section of our website at www.alkermes.com.

What are the Irish statutory financial statements and where can I access them?

As an Irish company, the Company is required to prepare statutory financial statements under the Companies Act and to deliver those financial statements together with reports of our directors and auditors thereon to shareholders of record in connection with our annual general meetings of shareholders.

These statutory financial statements cover our results of operations and financial position for the year ended prior to each annual general meeting of shareholders and are approved each year by the Board. There is no requirement under Irish law that such financial statements be approved by the Company’s shareholders, and no such approval will be sought at the Annual Meeting.

The Company’s Irish statutory financial statements for the year ended December 31, 2022, including the reports of the directors and auditors thereon, will be presented at the Annual Meeting in accordance with the requirements of the Companies Act. These financial statements and the related reports are available on the Annual Reports page of the Investors section of the Company’s website at www.alkermes.com. Shareholders may also request a printed copy of these statements and reports free of charge, by writing to our Secretary at Alkermes plc, Connaught House, 1 Burlington Road, Dublin 4, Ireland, D04 C576, Attention: Company Secretary.

Who do I contact if I have questions about the Annual Meeting?

If you have questions about how to vote your shares, please contact the firm assisting us with the solicitation of proxies:

Innisfree M&A Incorporated

Shareholders may call: +1 (877) 750-8334 (toll-free from the U.S. or Canada)

or +1 (412) 232-3651 (from other countries).

Banks and brokers may call collect: +1 (212) 750-5833.

We also invite shareholders to reach out to our Investor Relations team at investor_relations@alkermes.com.

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Important Notice Regarding the Internet and Electronic Availability of Proxy Materials for the Annual Meeting:

All shareholders have the ability to access this proxy statement and the Company’s Annual Report at http://www.proxydocs.com/ALKS or through the Investors section of our website at www.alkermes.com. Because we have elected to utilize the “full set delivery” option for proxy materials related to the Annual Meeting, we are delivering paper copies of our proxy materials to our shareholders as of the Record Date.

In addition, any shareholder may request to receive, on an ongoing basis, future proxy materials in printed form, by mail or electronically by email. A shareholder’s election as to the format for its receipt of proxy materials will remain in effect until such shareholder terminates such election.

Note Regarding Trademarks

We are the owner of various United States (“U.S.”) federal trademark registrations (“^®”) and other trademarks (“^TM”) and service marks (“^SM”), including ALKERMES^®, ALKERMES INSPIRATION GRANTS^®, ALKERMES PATHWAYS RESEARCH AWARDS^®, ARISTADA^®, ARISTADA INITIO^®, LYBALVI^® and VIVITROL^®. KEYTRUDA^® is a registered trademark of Merck Sharp & Dohme Corp. VUMERITY^® is a registered trademark of Biogen MA Inc., used by the Company under license. Other trademarks, trade names and service marks appearing in this proxy statement are the property of their respective owners. Solely for convenience, the trademarks, service marks and trade names in this proxy statement are referred to without the ^® and ™ symbols, but such references should not be construed as any indicator that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto.

Note Regarding Product References

Except as otherwise suggested by the context, (a) references in this proxy statement to “products” or “our products” include our marketed products, marketed products using our proprietary technologies, our licensed products, our product candidates, and product candidates using our proprietary technologies and (b) references in this proxy statement to the “biopharmaceutical industry” are used interchangeably with references to the “biotechnology industry” and/or the “pharmaceutical industry.”

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Background to the Solicitation

Executive Summary

The Company first engaged with Sarissa and Elliott Investment Management L.P. and its affiliates (“Elliott”) in 2020. These engagements resulted in the appointment of three directors supported by Elliott (Emily Alva, David Daglio and Brian McKeon) and one director designated by Sarissa (Cato Laurencin, M.D., Ph.D.). Each of these directors continues to serve on the Board.

In February 2023, the Company received a notice from Sarissa of its intent to nominate an additional three Sarissa director candidates for election to the Board. Two of the three Sarissa Nominees – Alexander Denner, Ph.D., Founder and Chief Investment Officer of Sarissa, and Sarah Schlesinger, M.D., an immunologist and Sarissa designee on the Innoviva, Inc. board of directors and a member of other boards of directors with significant Sarissa representation – were previously nominated by Sarissa for service on the Company’s Board in 2022. At that time, the Board unanimously determined not to nominate them for election to the Board. The third Sarissa Nominee – Patrice Bonfiglio, a Sarissa employee – had not served on a public company board of directors until her appointment as a director of Amarin plc in February 2023. The Board determined that the key attributes and experience of the three Sarissa Nominees were neither additive to the Board at this time nor consistent with those attributes and experience previously identified by the Board as important in a new director nominee, and therefore not in the best interests of the Company.

Since 2020 through the date of this proxy statement, members of the Company’s management team and Board have engaged extensively with Sarissa. Throughout, Sarissa’s primary focus has been its belief that it deserves direct representation on the Board. This has remained Sarissa’s primary objective even after its designation of Dr. Laurencin for election to the Board in 2021.

Engagement with Elliott

In December 2020, following constructive dialogue with many of the Company’s shareholders, including Elliott, and entry into a cooperation agreement with Elliott (the “Elliott Cooperation Agreement”), the Company announced its commitment to multi-year profitability targets, a review and optimization of the Company’s cost structure, potential monetization of non-core assets, and continued governance enhancements.

In connection with the December 2020 announcement, the Board continued its Board refreshment activities and appointed two new independent directors supported by Elliott – David Daglio, the former EVP, Chief Investment Officer and Executive director of Mellon Investments Corporation, and Brian McKeon, the Executive Vice President, Chief Financial Officer and Treasurer of IDEXX Laboratories, Inc. – who bring to the Board investor perspectives as well as strong financial and operational expertise. The Company also announced that two longer-serving directors planned to retire from the Board at the close of the Company’s 2021 annual general meeting of shareholders (the “2021 Annual Meeting”). As part of the Elliott Cooperation Agreement, the Board worked with Elliott to mutually identify and appoint one additional independent director in May 2021, Emily Alva, a financial, strategic and business advisor with more than two decades of experience, including as a former investment banker and M&A partner at Lazard.

The Elliott Cooperation Agreement also included agreed corporate governance enhancements, including a commitment by the Company to recommend declassification of the Board, and the establishment of the Financial Operating Committee to oversee, among other things, achievement of the Company’s profitability targets and potential monetization of the Company’s non-core assets. All three of the Elliott-supported directors have served as three of the five members of this committee since its formation.

Engagement with Sarissa

Since 2009, Dr. Denner has served on the board of directors of Biogen Inc. (“Biogen”), which exclusively licenses and globally commercializes VUMERITY^®, a drug product that Alkermes developed and that was approved by the FDA in October 2019. Biogen pays Alkermes manufacturing fees for the supply of VUMERITY and royalties on net sales of VUMERITY. The companies are in frequent communication and discussion, including some in which the Company and Biogen have disagreed, regarding these manufacturing and commercialization activities.

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2020

On February 14, 2020, Sarissa filed a Schedule 13F disclosing ownership of approximately 2.33% of the outstanding ordinary shares of the Company as of December 31, 2019. The next day, Mr. Pops emailed Dr. Denner, acknowledging that Sarissa recently became a shareholder of the Company and suggesting a meeting. 

Between August 2020 and December 2020, representatives of the Company had conversations with representatives of Sarissa, during which they discussed, among other things, the evolution of the Company’s business and its strategic priorities, and during which Dr. Denner commended Mr. Pops’ leadership. Feedback shared by Sarissa representatives during these conversations was communicated by management to the Board.

On December 4, 2020, the Company received notice from Sarissa of its intent to nominate Dr. Denner for election to the Company’s Board (the “First Sarissa Nomination Notice”).

Later that day, Dr. Denner and Mr. Pops held a virtual meeting. Mr. Pops expressed surprise to receive the notice given that Dr. Denner had not previously expressed any concerns about the Company. Dr. Denner indicated that he considered the notice a placeholder and that he thought he could be helpful on the Board. Mr. Pops inquired whether Dr. Denner would be willing to enter into a confidentiality agreement with the Company prior to their next discussion, and Dr. Denner agreed.

On December 7, 2020, Mr. Pops and Dr. Denner held a virtual meeting during which Mr. Pops informed Dr. Denner of the Company’s engagement with Elliott. Dr. Denner expressed frustration that Elliott was engaging with the Company despite not having publicly disclosed an ownership stake in the Company.

On December 10, 2020, after multiple productive engagements with Elliott, the Company announced the Elliott Cooperation Agreement, its commitment to long-term profitability targets and other governance and financial enhancements, and the appointment of two new independent directors, Mr. Daglio and Mr. McKeon.

2021

Between February 2021 and March 2021, Mr. Pops and Dr. Denner had numerous engagements. During these conversations and email communications, Mr. Pops described the Company’s ongoing board refreshment efforts. Mr. Pops solicited Dr. Denner’s input with respect to the specific skills and experience that he believed would be additive to the Board and his recommendations of specific individuals for consideration. Throughout this period, Mr. Pops relayed to the Board the substance of these interactions and the perspectives shared by Dr. Denner.

Throughout April 2021, representatives of the Company had numerous engagements with representatives of Sarissa during which they negotiated the details of a potential settlement agreement.

On April 24, 2021, Sarissa formally withdrew the First Sarissa Nomination Notice.

On April 29, 2021, the Company and Sarissa announced a settlement agreement, pursuant to which the Company granted Sarissa a right to designate one director for appointment to the Board from a predetermined list of candidates identified by Sarissa, with such right exercisable between October 30, 2021 and February 28, 2022 (the “Sarissa Settlement Agreement”).

On May 20, 2021, the Company announced the appointment to the Board of a new independent director, Ms. Alva, pursuant to the Elliott Cooperation Agreement.

On September 27, 2021, Mr. Gaffin, Chief Legal Officer of the Company, spoke with Mr. DiPaolo, Senior Partner and General Counsel of Sarissa. Mr. DiPaolo noted that Dr. Denner had identified a potential candidate for the Board, who was later disclosed to be Dr. Laurencin.

Between September 30, 2021 and November 18, 2021, representatives of the Company had numerous engagements with representatives of Sarissa, including with respect to Dr. Laurencin’s candidacy and to solicit Dr. Denner’s perspectives on the business.

On November 19, 2021, following an interview process led by the Nominating and Corporate Governance Committee, the Company announced the appointment of Dr. Laurencin to the Board pursuant to the Sarissa Settlement Agreement.

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2022

On January 3, 2022, approximately six weeks after the Board appointed Dr. Laurencin as director designee of Sarissa, Mr. DiPaolo emailed Mr. Gaffin requesting time to speak. Mr. Gaffin spoke with Mr. DiPaolo that same day. Mr. DiPaolo noted that Dr. Denner was planning to reach out to Mr. Pops to discuss Sarissa’s intent to nominate Dr. Denner and Dr. Schlesinger for election to the Board at the 2022 Annual Meeting.

On January 4, 2022, Mr. DiPaolo emailed Mr. Gaffin an electronic copy of Sarissa’s notice of its intention to nominate Dr. Denner and Dr. Schlesinger (the “2022 Sarissa Nominees”) for election to the Company’s Board at the 2022 Annual Meeting (the “Second Sarissa Nomination Notice”).

On January 5, 2022, Mr. Pops and Dr. Denner had a telephone conversation during which Dr. Denner expressed his belief that he could be helpful as a director to help assure other shareholders that the Company had not mishandled the situation related to the partial termination in respect of two license agreements with Janssen Pharmaceutica N.V. (“Janssen”). Mr. Pops indicated that he valued Dr. Denner’s feedback and would be happy to collaborate with him once again in identifying director candidates with the attributes and skills that would be additive to the Board given its current composition and the Company’s current strategic priorities.

On the morning of January 7, 2022, Mr. DiPaolo emailed Mr. Gaffin to indicate that a copy of the Second Sarissa Nomination Notice would be delivered to the Company’s registered offices, as required by the advance notice requirements of the Company.

On January 10, 2022, Sarissa filed a Schedule 13D disclosing the Second Sarissa Nomination Notice and beneficial ownership of approximately 8.67% of the outstanding ordinary shares of the Company.

On January 18, 2022, Mr. Pops emailed Dr. Denner requesting a telephone conversation. Mr. Pops’ assistant exchanged emails with Dr. Denner’s assistant, who agreed to a tentative date and indicated that she would confirm a meeting time. No such confirmation was made and Dr. Denner did not make himself available to speak with Mr. Pops again until nearly two months later.

On March 2, 2022, Mr. DiPaolo and Mr. Gaffin spoke twice. Mr. Gaffin reiterated the Company’s interest in engaging with Dr. Denner in respect of the Second Sarissa Nomination Notice and inquired why Dr. Denner chose not to respond to Mr. Pops’ attempts at outreach. Mr. DiPaolo responded that he was not privy to Dr. Denner’s rationale.

On March 3, 2022, Mr. Pops again emailed Dr. Denner noting that he had not heard back from him since early January. Mr. Pops remarked that he believed they should connect.

On March 10, 2022, in lieu of the proposed virtual meeting, Mr. Pops traveled to Greenwich, Connecticut to meet Dr. Denner at Sarissa’s offices in an effort to foster a more constructive dialogue. They met for two hours and discussed the Company’s business, including R&D activities, commercial performance and cost optimization efforts. Dr. Denner stated that Mr. Pops was doing a “good job”. Mr. Pops noted that certain longer-serving members of the Board might consider retiring and that the Board had identified the need for a director candidate, independent of Sarissa and the Company, with deep pharmaceutical drug development and R&D portfolio management experience, with a specific need for neuroscience expertise. Mr. Pops asked for Dr. Denner’s assistance in identifying such a director candidate and suggested that Sarissa’s designation of such a candidate for appointment to the Board could serve as the basis for a second settlement agreement between Sarissa and the Company. Mr. Pops and Dr. Denner discussed two such potential candidates that the Company had identified, including Dr. Christopher Wright, M.D., Ph.D. Dr. Denner noted that he was, coincidentally, planning to speak with Dr. Wright in the upcoming days.

On March 14, 2022, Mr. Pops emailed Dr. Denner to ask for his opinion on Dr. Wright as a candidate for the Board and to learn Dr. Denner’s interest in speaking with the other director candidate identified by the Company and its director recruitment firm.

On March 22, 2022, having not received a reply from Dr. Denner, Mr. Pops sent Dr. Denner another email asking that they reconnect to discuss the candidacy of Dr. Wright and the other director candidate previously identified, and to explore the feasibility of a settlement agreement.

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Between March 22, 2022 and March 25, 2022, Mr. Pops’ assistant sent multiple emails to Dr. Denner’s assistant in order to arrange a time for Dr. Denner and Mr. Pops to speak. On March 25, 2022, Dr. Denner’s assistant responded that she was unable to schedule a time for such call.

On March 25, 2022, Dr. Denner replied to Mr. Pops’ email from March 22, 2022. Dr. Denner stated that, after their discussion in Greenwich, he was considering Sarissa representatives as potential candidates for the Board: “Patrice Bonfiglio and also me!”

On March 26, 2022, Mr. Pops replied to Dr. Denner’s email asking for his availability to speak during the weekend.

On March 28, 2022, Dr. Denner replied and Mr. Pops and Dr. Denner spoke by telephone later that day. Mr. Pops reiterated his desire to engage in constructive discussions with Dr. Denner about how to identify director nominees, independent of Sarissa and Alkermes, that could add neuroscience, pharmaceutical drug development and R&D portfolio capital allocation expertise and experience to the Board. In response, Dr. Denner praised Ms. Bonfiglio, a Sarissa employee whom Dr. Denner conceded did not have any public company board experience. Dr. Denner dismissed the potential candidacies of Dr. Wright and the other neuroscience expert that he and Mr. Pops had discussed during their in-person meeting. Mr. Pops reiterated his concerns around adding the Sarissa director nominees to the Board due to the mismatch of their skillsets relative to the Board’s identification of the need for a director nominee with substantial neuroscience, pharmaceutical drug development and R&D portfolio management experience, given the Company’s strategic focus in neuroscience. Feedback from this discussion was relayed to the Nominating and Corporate Governance Committee and the full Board.

On May 12, 2022, Mr. DiPaolo reached out to Mr. Gaffin for a discussion, during which Mr. DiPaolo continued to praise Dr. Denner as an ideal board member and expressed his belief that Dr. Denner’s appointment to the Board would serve to increase the Company’s share price and help the Company gain credibility.

On May 17, 2022, the Nominating and Corporate Governance Committee recommended to the Board that Dr. Wright, a neurologist and neuroscientist with more than 20 years of clinical and drug development experience, be appointed to the Board as a Class II director and be nominated for re-election by the Company’s shareholders at the 2022 Annual Meeting.

Between May 17, 2022 and May 26, 2022, representatives of the Company and Sarissa had numerous communications, including a virtual meeting between Mr. Pops and Dr. Denner, with respect to the Board’s refreshment activities and a potential amicable resolution, the Board’s desire to collaborate with Sarissa in lieu of a contested election and the Company’s anticipated timelines for filing of its preliminary proxy materials for the 2022 Annual Meeting.

On May 24, 2022, the Board appointed Dr. Wright to the Board (effective immediately) and appointed non-employee director Nancy Wysenski as the new Lead Independent Director of the Board (effective as of the close of the 2022 Annual Meeting). In addition, previous Lead Independent Director David Anstice AO and Wendy Dixon, Ph.D., the Company’s two longest-serving non-employee directors, announced their decisions to retire from the Board as of the close of the 2022 Annual Meeting.

On May 25, 2022, Dr. Denner requested to speak with the Board.

On May 26, 2022, Mr. Pops emailed Dr. Denner and explained that the Nominating and Corporate Governance Committee, which was composed at the time of three independent directors – Drs. Dixon and Snyderman and the Sarissa designee, Dr. Laurencin – reviewed and discussed the qualifications of the two 2022 Sarissa Nominees, including the detailed information about each such nominee that accompanied the Second Sarissa Nomination Notice, and unanimously determined that the 2022 Sarissa Nominees’ key attributes and experience were neither additive to the Board nor consistent with those attributes and experiences previously identified by the Board as important in a new director nominee in order to advance the long-term strategy of the Company and create shareholder value. Mr. Pops also stated that the Board would be happy to schedule a time to hear Dr. Denner’s perspectives once the current dispute is resolved.

Also on May 26, 2022, the Company filed its preliminary proxy statement.

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On May 27, 2022, Sarissa issued a press release (the “May 27 Press Release”) regarding its engagement with the Company in which Sarissa made a number of false and misleading statements and mischaracterized actions taken by the Board.

That same day, Mr. Pops emailed Dr. Denner and, noting his disappointment with the May 27 Press Release, corrected misstatements made by Sarissa. Additionally, in response to Dr. Denner’s request, Mr. Pops informed Dr. Denner that independent directors of the Board were willing to listen to Dr. Denner’s views and explain their decision-making process in respect of the 2022 Sarissa Nominees.

On June 3, 2022, Mr. Anstice, the Board’s outgoing Lead Independent Director, Ms. Wysenski, the Board’s incoming Lead Independent Director, Drs. Laurencin (a Sarissa-designated director) and Snyderman, and Mr. Daglio (an Elliott-supported director), held a videoconference call with Dr. Denner. During the call, the independent directors explained their decision-making process in respect of the 2022 Sarissa Nominees. Dr. Denner shared his perspectives on the Company and continued to insist that he and Dr. Schlesinger should be appointed to the Board. The directors present committed to Dr. Denner that they would relay his perspectives to the other independent directors of the Board.

Between June 5, 2022 and June 6, 2022, two independent directors, Mr. Anstice and Ms. Wysenski, engaged with Dr. Denner, including with respect to the Board’s discussion of the perspectives raised by Dr. Denner during the June 3, 2022 call and the Board’s subsequent determination, consistent with its earlier determination, that appointing the 2022 Sarissa Nominees would not be in the best interests of the Company and all shareholders.

On June 6, 2022, the Company filed its definitive proxy statement for the 2022 Annual Meeting.

On July 6, 2022, the day before the 2022 Annual Meeting, Sarissa issued a press release related to its engagement with the Company and Sarissa’s intention to vote “FOR” each director on the Company’s slate at the 2022 Annual Meeting. In such press release, Sarissa made additional false and misleading statements and mischaracterized actions taken by the Company. Sarissa also threatened that if a Sarissa representative is not soon appointed to the Board, Sarissa would take steps under Irish law to call an extraordinary general meeting of shareholders to selectively remove and replace members of the Board.

Also on July 6, 2022, Sarissa filed a Schedule 13D reporting its press release issued on July 6, 2022, that indicated “how the Reporting Persons intend to vote at the upcoming annual meeting of the Issuer and the reasons therefor”. Sarissa also disclosed beneficial ownership of approximately 8.55% of the outstanding ordinary shares of the Company.

On July 7, 2022, at the Company’s 2022 Annual Meeting, the Company’s shareholders approved all of the Company’s proposals, including election of each of the Board’s director nominees, with support ranging from 86% to 99% of the votes cast.

On October 7, 2022, Sarissa filed a Schedule 13D indicating its intent to enhance its buying power and opportunity to buy additional shares and derivative securities of the Company in order to increase its beneficial ownership of the Company. Sarissa also disclosed beneficial ownership of approximately 8.55% of the outstanding ordinary shares of the Company.

On December 7, 2022, the Company reached out to Dr. Denner as part of its routine shareholder outreach activities and offered Sarissa an opportunity to continue engaging with independent members of the Board.

On December 21, 2022, three independent members of the Board –Ms. Wysenski, our Lead Independent Director, Mr. Daglio and Mr. McKeon (two Elliott-supported directors)– held a meeting with a number of Sarissa representatives, including Dr. Denner, Ms. Bonfiglio and Mr. DiPaolo. During this meeting, the independent directors asked the Sarissa representatives if they had any constructive feedback on the Company’s business and performance that could be relayed to management and the Board. Dr. Denner and Mr. DiPaolo emphasized repeatedly Sarissa’s continued desire for additional Sarissa representation on the Board.

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2023

On January 5, 2023, Dr. Denner emailed Ms. Wysenski inquiring regarding a discussion with the Nominating and Corporate Governance Committee regarding Sarissa’s request to have “Sarissa people” join the Board.

Later that day, Ms. Wysenski informed Dr. Denner that she was in the process of following up with the full Board regarding such discussion and would be in touch once that occurred.

On January 6, 2023, the Company announced that it had received a favorable interim award (the “Initial Interim Award”) in its arbitration proceedings with Janssen in respect of Janssen’s partial termination in the United States of two license agreements with the Company, which the Company announced in November 2021. In the Initial Interim Award, the arbitral tribunal agreed with Alkermes’ position that, while Janssen may terminate the agreements, Janssen may not continue to sell Products (as defined in the agreements) developed during the term of the agreements without paying royalties pursuant to the terms of the respective agreements. Dr. Denner had previously cited the Janssen partial terminations as a reason for deciding to submit the Second Sarissa Nomination Notice in 2022.

On January 19, 2023, Ms. Wysenski emailed Dr. Denner to notify him that the full Board had been updated on the substance of the December conversation between representatives of Sarissa and representatives of the Board and that the Company would reach out to Sarissa soon to schedule a call between Sarissa and representatives of the Nominating and Corporate Governance Committee, as requested by Sarissa.

Between January 25, 2023 and January 31, 2023, the Company reached out to Dr. Denner’s office several times to coordinate time for a call between Sarissa and members of the Nominating and Corporate Governance Committee, as requested by Sarissa.  

On February 2, 2023 at 11:42 am, Dr. Denner’s assistant responded to the Company’s January 31, 2023 email, asking that the meeting between Sarissa and the Nominating and Corporate Governance Committee be held at 3:00 pm that same afternoon.

Despite the short notice, that afternoon, three of the four members of the Nominating and Corporate Governance Committee held a meeting with representatives of Sarissa, including Dr. Denner and Ms. Bonfiglio. During this discussion, Sarissa reasserted its desire for representation on the Board, emphasizing that Sarissa deserved to have seats on the Board by virtue of its shareholdings alone. The members of the Nominating and Corporate Governance Committee reiterated to Dr. Denner the robust and independent process that it and the Board follow in evaluating the composition and effectiveness of the Board and assessing and recommending director candidates for election to the Board.

On Friday, February 3, 2023, Sarissa delivered to the Company a notice of its intention to nominate the three Sarissa Nominees – Dr. Denner, Dr. Schlesinger and Ms. Bonfiglio – for election to the Company’s Board at the 2023 Annual Meeting (the “Third Sarissa Nomination Notice”).

On February 6, 2023, Sarissa filed a Schedule 13D disclosing the Third Sarissa Nomination Notice, noting that Sarissa has been “…discussing Sarissa Capital representation on the Board with the Issuer’s independent directors for many months” and that such notice “reserves the Reporting Person’s right to seek Sarissa Capital representation directly from fellow shareholders at the upcoming annual meeting in the event the independent directors choose not to add Sarissa Capital representation to the Board”. Sarissa also disclosed beneficial ownership of approximately 8.54% of the outstanding ordinary shares of the Company.

On March 1, 2023, the Company emailed the office of Dr. Denner to notify Sarissa that the Nominating and Corporate Governance Committee would conduct individual interviews with each of the three director nominees and offer windows of time during early March during which such interviews could be conducted. A representative of Sarissa promptly responded to this request to schedule interviews with Sarissa Nominees Dr. Schlesinger and Ms. Bonfiglio; however, no similar availability for such an interview was provided for Dr. Denner.

On March 9, 2023, all members of the Nominating and Corporate Governance Committee separately interviewed each of Dr. Schlesinger and Ms. Bonfiglio.

Also on March 9, 2023, following the interviews with Dr. Schlesinger and Ms. Bonfiglio, Sarissa responded with Dr. Denner’s availability for an interview.

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On March 17, 2023, all members of the Nominating and Corporate Governance Committee interviewed Dr. Denner.

On April 17, 2023, three independent members of the Board – Ms. Wysenski, our Lead Independent Director, Dr. Snyderman, chair of our Nominating and Corporate Governance Committee, and Ms. Alva, an Elliott-appointed director and member of the Nominating and Corporate Governance Committee, held a meeting with Dr. Denner. During this meeting, the directors relayed to Dr. Denner the process undertaken by the Nominating and Corporate Governance Committee and the Board in assessing the candidacy of the Sarissa Nominees and the decision of the Board not to endorse the Sarissa Nominees for election to the Board. The directors also reiterated that the Board would like to continue to engage with Sarissa in a constructive manner and offered examples of potential opportunities for constructive engagement going forward. The directors stated that the Board was open to creative options to come to an amicable resolution beyond these examples and asked that Dr. Denner consider and suggest any other solutions that may be acceptable to him to avoid a potential proxy contest.

On April 19, 2023, Ms. Wysenski emailed Dr. Denner to follow up on the discussion earlier that week, noting appreciation for the constructive nature of the discussion and that the substance of the discussion would be relayed to the full Board. She also asked Dr. Denner whether he had any further ideas that could help support a collaborative dialogue, noting that the Board would welcome such ideas in advance of the Company's filing of its proxy statement in the near term.

On April 22, 2023, Dr. Denner responded to Ms. Wysenski, asking, among other things, what harm would arise from putting Sarissa’s nominees on the Board. Dr. Denner expressed his hope to continue the dialogue, but did not suggest any additional constructive solutions to avoid a proxy fight.

On April 25, 2023, the Company announced receipt of a second favorable interim award in its arbitration proceedings with Janssen in respect of Janssen’s partial terminations in the United States of two license agreements with the Company. Dr. Denner had previously cited the Janssen partial terminations as a reason for deciding to submit the Second Sarissa Nomination Notice in 2022.

On April 25, 2023, Ms. Wysenski emailed Dr. Denner, stating again the Board’s desire to continue the dialogue with Sarissa and its hope to reach a constructive resolution. Ms. Wysenski asked Dr. Denner again to respond with any ideas that could help support a collaborative dialogue. She also informed him that the Company intended to file its proxy materials shortly. Ms. Wysenski received no reply from Dr. Denner.

On May 2, 2023, Ms. Wysenski again emailed Dr. Denner, expressing a desire to reach an amicable resolution before the Company files its proxy materials, which she informed him was planned to occur in short order. The email reiterated the Board’s offer to establish regular dialogue with Sarissa as part of a settlement and its willingness to consider potential alternative solutions in lieu of a contested election, and asked Dr. Denner to respond with any ideas he has for doing so.

On May 3, 2023, Dr. Denner replied to Ms. Wysenski, noting Sarissa’s desire to settle and that he had ideas for discussion, but not providing any description or details of such ideas or offering any times for discussion.

On May 4, 2023, Ms. Wysenski emailed Dr. Denner to request that he share, in writing, any actionable ideas for a potential settlement so that she could relay them to the full Board for consideration. She also noted that the Company intended to file its preliminary proxy statement on May 8, 2023 and reiterated that the Company remained open to an amicable resolution, noting that the filing of its preliminary proxy materials would not preclude continuation of the dialogue with Sarissa.

On May 7, 2023 around 10 pm, Dr. Denner replied to Ms. Wysenski regarding potential further discussions. On May 8, 2023, Ms. Wysenski responded to Dr. Denner acknowledging his response and noting that the Board remains open to continuing to explore possible ideas for settlement with Sarissa. Ms. Wysenski informed Dr. Denner that the Company would proceed to file its preliminary proxy materials later that day as planned, and reiterated that doing so would not preclude a potential settlement.

On May 8, 2023, the Company filed its preliminary proxy statement.

On May 15, 2023, Sarissa filed its preliminary proxy statement.

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On May 16, 2023, four independent members of the Board – Ms. Wysenski, Dr. Snyderman, Ms. Alva, and Mr. Daglio – held a meeting with Dr. Denner and other Sarissa representatives during which potential ideas for settlement were discussed. The directors noted that the substance of the discussion would be relayed to the full Board.

On May 18, 2023, Ms. Wysenski emailed Dr. Denner, reiterating the Board’s willingness to establish regular meetings with Sarissa representatives as the construct of a settlement. She also noted that the Board discussed the proposed settlement concept advanced by Sarissa and determined that it did not address the substantive considerations of the Board in determining not to endorse the Sarissa director candidates and was not in the best interests of Alkermes’ shareholders, but that the Board remained open to exploring additional ideas for potential settlement.

On May 19, 2023, the Company filed a revised preliminary proxy statement.

On May 22, 2023, Sarissa filed a revised preliminary proxy statement.

On May 25, 2023, the Company filed this definitive proxy statement.

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PROPOSAL 1

ELECTION OF DIRECTORS

(Ordinary resolutions)

Our Board, upon the recommendation of the Nominating and Corporate Governance Committee, has nominated each of the following Board Nominees for election as Class II and Class III directors, as applicable, for a one-year term expiring at the close of the Company’s 2024 annual general meeting of shareholders or until their successor is appointed or their earlier resignation or removal:

⁺Ages presented are as of May 15, 2023.

*Represents the number of public company boards on which the director serves in addition to our Board.

Term and Board Declassification: Our Board is currently divided into three classes of directors. Historically, each class of directors was elected to serve a staggered three-year term. In June 2021, after considering feedback from our shareholders, our Board asked our shareholders to approve, and our shareholders approved, certain amendments to our Articles of Association that serve to declassify our Board over a three-year period. Per our Articles of Association (as so amended), since the 2022 Annual Meeting, each class of directors that is up for election is eligible for a one-year term. Accordingly, any director nominee elected pursuant to this Proposal 1 will be elected to serve a one-year term expiring at our 2024 annual general meeting of shareholders. The June 2021 amendments to our Articles of Association did not impact the terms of directors elected at or prior to our 2021 annual general meeting of shareholders, such that the Class I directors who were elected to a three-year term in 2021 will complete their three-year terms, which expire at our 2024 annual general meeting of shareholders. As of our 2024 annual general meeting of shareholders, our Board will be fully declassified.

Contested Election: On February 3, 2023, Sarissa Offshore delivered a notice to the Company of its intent to nominate three director candidates for election to the Board at the Annual Meeting. The Nominating and Corporate Governance Committee and the Board considered the candidacy of each of the Sarissa Nominees and, in making its recommendations for the directors to be elected at the Annual Meeting, carefully considered the best interests of the Company and its shareholders. THE BOARD DOES NOT ENDORSE THE SARISSA NOMINEES AND RECOMMENDS THAT YOU ONLY VOTE “FOR” THE SEVEN BOARD NOMINEES AND THAT YOU DO NOT MARK A VOTE WITH RESPECT TO ANY SARISSA NOMINEE. You may receive a proxy statement, blue proxy card and other solicitation materials from Sarissa. You should disregard those materials and only vote on a WHITE proxy card that you receive from the Company.

Recommendation: The Board recommends that you vote FOR the election of each of the seven Board Nominees. As described in detail below, each of the Board Nominees has considerable professional and

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business expertise. Our Board’s recommendation is based on its carefully considered judgment that the experience, qualifications, attributes and skills of the Board Nominees qualify them to serve on our Board.

The Board has been informed that each of the Board Nominees has consented to serve as a nominee, to serve as a director if elected, and to be named as a nominee in this proxy statement. If, however, any Board Nominee should, prior to the Annual Meeting, decline to serve or become unavailable for election at the Annual Meeting, an event which the Board does not anticipate, the named proxy holders intend to vote for such other director nominee or nominees as may be designated by the Board, unless the Board reduces the number of directors which comprise the Board accordingly.

Plurality Voting Standard: Our Articles of Association provide for a plurality voting standard for contested director elections. There are seven available director positions for election as Class II and Class III directors, as applicable, at the Annual Meeting. Because this is a contested election in which the number of director nominees exceeds the number of available director positions, only those directors who receive the highest number of votes cast in favor of their election on their respective resolution (meaning the number of shares voted “FOR” each nominee) in person or by proxy at the Annual Meeting will be elected to serve on the Board. Under this plurality voting standard, votes to “WITHHOLD” on director nominees will have no effect on the election of director nominees. Broker non-votes will have no effect on the election of director nominees because they are not considered to be votes cast.

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Board of Directors

Board Size and Structure

In accordance with our Articles of Association, the Board reviews the appropriateness of the size of the Board from time to time and increases or decreases the number of director seats on the Board as it deems appropriate. In May 2022, the Board approved (i) effective immediately, an increase in the size of the Board from 12 directors to 13 directors and appointed Dr. Wright to fill the newly created vacancy on the Board, and (ii) effective upon the retirement from the Board of former directors David W. Anstice AO and Wendy L. Dixon, Ph.D. at the close of the 2022 Annual Meeting, a decrease in the size of the Board from 13 directors to 11 directors.

Board Declassification: In accordance with our Articles of Association, our Board is currently divided into three classes of directors. Historically, each class of directors was elected to serve a staggered three-year term. In June 2021, after considering feedback from certain of our shareholders, we asked our shareholders to approve, and our shareholders approved, certain amendments to our Articles of Association that serve to declassify our Board over a three-year period. Accordingly, beginning with the 2022 Annual Meeting, each class of directors that is up for election is eligible for a one-year term. A director elected by the Board to fill a vacancy in a class will serve for the remainder of the full term of that class and until the director’s successor is elected and qualified, or, if sooner, until their death, resignation, retirement, disqualification or removal.

The Board Nominees and continuing directors are currently divided among the classes as follows:

As discussed below, the composition and functioning of our Board and each of its committees complies with all applicable rules and regulations of the Nasdaq Stock Market (“Nasdaq” and such rules and regulations, the “Nasdaq Rules”) and requirements of the Exchange Act and other SEC regulations.

Independence of Members of the Board

In accordance with our Corporate Governance Guidelines, not less than a majority of the Board must meet the independence requirements set forth in the Nasdaq Rules. The Board annually makes a determination as to whether each director is “independent” as set forth in the applicable provisions of the Nasdaq Rules and the Exchange Act and the rules promulgated thereunder. To assist in making its determination, the Board periodically reviews each director’s status as an independent director, including soliciting information from each director regarding whether such director, or any member of their immediate family, had a direct or indirect material interest in any transactions involving the Company, was involved in a debt relationship with the Company, received personal benefits outside the scope of such person’s normal compensation or has any other relationship with the Company that, in the judgment of the Board, would interfere with such director’s exercise of independent judgment in carrying out such director’s responsibilities as a director.

Based on the information provided by each of the Company’s directors, the Board has determined that, with the exception of Richard F. Pops (our CEO), each of our current directors and each director who served on our Board during any part of 2022 is independent, and that each member of each standing committee of our Board—the Audit and Risk Committee, Compensation Committee and Nominating and Corporate Governance Committee—is (or was at the time of their service on our Board) “independent” (as defined in the applicable provisions of the Nasdaq Rules and the Exchange Act and the rules promulgated thereunder). There are no family relationships among any of our directors, director nominees or executive officers.

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Board Leadership Structure

Chairperson of the Board. The chairperson of the Board presides at meetings of the shareholders and the Board and is primarily responsible for overseeing the development of the Company’s strategic goals and objectives. Mr. Pops has served as Chairman of the Board since 2011.

In deciding to appoint Mr. Pops to the combined role of CEO and Chairman, the Board recognized Mr. Pops’ ability to provide effective, consistent and continuous leadership to both the Board and the Company, his ability to align the strategic objectives of both management and the Board, his extensive knowledge of the Company’s operations and the industry and markets in which the Company operates and competes, and his ability to promote communication and synchronize activities between the Board and senior management.

Lead Independent Director. Recognizing the equal importance of effective independent oversight of the Company, the independent members of the Board annually elect an independent non-employee director to serve as the Lead Independent Director of the Board, whose leadership responsibilities include, among others:

A current copy of our Charter of the Lead Independent Director is available on the Corporate Governance page of the Investors section of our website at www.alkermes.com.

Effective July 2022, the Board appointed Nancy J. Wysenski to serve as Lead Independent Director of the Board. In this capacity, Ms. Wysenski has played an active and engaged leadership role in activities and meetings of the Board, including executive sessions of the independent directors, and has participated alongside Company management in shareholder engagement activities.

Assessment of Board Leadership Structure. The Board periodically reviews its composition and leadership structure. The Board believes that its current leadership structure provides an efficient and effective balance between management and independent leadership and is the most appropriate Board leadership structure for the Company at this time.

Committees. The Board delegates substantial responsibilities to its three standing committees—Audit and Risk, Compensation, and Nominating and Corporate Governance—each of which is comprised solely of independent directors and led by an independent chair, and to other committees that the Board may establish from time to time, including the recently constituted Financial Operating Committee. These committees and their respective oversight responsibilities are discussed in detail below in the section entitled “The Role of the Board and its Committees” beginning on page 45 of this proxy statement.

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Director Diversity, Qualifications and Experience

The Nominating and Corporate Governance Committee strives to ensure that the composition of the Board reflects an appropriate diversity of tenure, viewpoints, financial expertise, industry experience and skills, and personal characteristics such as age, gender, race, ethnicity and geographic or cultural backgrounds, and periodically reviews and updates the Company’s criteria and desired qualifications for nomination to the Board to reflect this goal.

Consistent with this approach, in 2019, the Board codified in our Corporate Governance Guidelines our practice, also known as the “Rooney Rule”, of requiring that diverse candidates, including candidates who are women and candidates from underrepresented communities, be included in any pool from which nominees for a director opening are selected. For additional discussion of our director criteria and nomination processes, see the section entitled “Policies Governing Director Nominations, Evaluations and Tenure” on page 52 of this proxy statement.

Our Board has a strong representation of directors who are diverse in terms of age, self-identified gender and race/ethnicity, and a mix of newer and longer-tenured directors, providing what we consider to be an appropriate balance of experience, institutional knowledge, fresh perspectives and skillsets.

The following graphics reflect the composition of the Board following the Annual Meeting, assuming the re-election of each of the seven Board Nominees.

Board Diversity Matrix

The following table provides certain self-identified personal characteristics of our Board members, in accordance with Rule 5605(f) of the Nasdaq listing standards:

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Board Skills Matrix

The following table highlights the specific skills, qualifications, and other attributes of our Board Nominees and continuing directors. The lack of a mark for a particular item for a director does not mean the director lacks that skill or qualification; rather, a mark indicates a specific area of focus or expertise of such director on which the Board relies. Additional information about each director’s background, business experience and other matters, including a description of how each individual’s experience qualifies him or her to serve on the Board, is provided below, beginning on the following page of this proxy statement.

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Board Nominee Biographical Information

The following descriptions set forth additional information regarding the Board Nominees, each of whom contributes significantly to the diversity of specific experience, skills and characteristics of our Board.

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Continuing Director Biographical Information

The following descriptions set forth additional information regarding our continuing directors, each of whom contributes significantly to the diversity of specific experience, skills and characteristics of our Board.

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The Role of the Board and its Committees

The Company’s business, property and affairs are managed under the direction of the Board. Members of the Board are kept informed of the Company’s business through discussions with the CEO and other officers of the Company, review of materials provided to them, visits to the Company’s facilities and participation in meetings of the Board and its committees and the Company’s annual general meetings of shareholders.

The Board has delegated to the CEO, working with the other executive officers of the Company, the authority and responsibility for managing the business of the Company in a manner consistent with the standards, values and practices of the Company, and in accordance with any specific plans, instructions or directions of the Board. The CEO and management are responsible for seeking the advice, and in appropriate situations, the approval, of the Board with respect to certain actions to be undertaken by the Company.

The Board’s Role in Oversight of Risks and Opportunities

Assessing and managing risks and opportunities is the responsibility of our management, and our Board oversees and reviews various aspects of the Company’s processes for management of such risks and opportunities. The Board executes this oversight responsibility directly and through its committees, including as set forth below:

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In performing their oversight functions, the Board and each Board committee has full access to management, including our Chief Risk Officer and our Chief Compliance Officer, and the ability to engage outside advisors.

The Committees of the Board

The Board currently has three standing committees: Audit and Risk Committee, Compensation Committee, and Nominating and Corporate Governance Committee, each of which is comprised entirely of independent directors. The Board may also, from time to time, form new committees or subcommittees, such as the recently constituted Financial Operating Committee, based on Company circumstances or when a desire for a more focused committee is identified. The Board may also disband current committees or subcommittees as it deems appropriate.

The Board is responsible for the appointment of committee members and relies on the Nominating and Corporate Governance Committee to recommend to the Board candidates for such appointments, and candidates to serve as the chairs of such committees. Each committee of the Board has the authority to engage outside experts, advisors and counsel, or to establish subcommittees, in each case to the extent it considers appropriate to assist the committee in its work.

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Each of the standing committees of the Board, and the Financial Operating Committee, has a written charter, approved by the Board, which describes the committee’s general authority and responsibilities. Each standing committee of the Board undertakes an annual review of its charter and works with the Board to make such revisions as it and the Board consider appropriate.

A current copy of the charters for each of the standing committees and the Financial Operating Committee is available on the Corporate Governance page of the Investors section of our website at www.alkermes.com.

The chair of each Board committee, in consultation with the Chairman of the Board and appropriate members of management, determines the frequency and length of each committee meeting and works with management to develop the agenda for each meeting. The agendas and meeting minutes of the Board committees are available to the full Board, and other Board members are welcome to attend Board committee meetings, except that non-independent directors are not permitted to attend the executive sessions of any standing Board committee. Each Board committee regularly reports to the Board concerning its activities.

Audit and Risk Committee

In compliance with the Sarbanes-Oxley Act of 2002, the Board has determined based on available facts and circumstances that Mr. Wilson is an “audit committee financial expert” as defined by the SEC. 

The Audit and Risk Committee’s responsibilities include:

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The Audit and Risk Committee engages and determines compensation for advisers as necessary and directs the distribution of funding provided by the Company to such advisers. The Audit and Risk Committee evaluates the performance of the independent auditor and accounting firm, ensures regular rotation of the audit partners from the independent auditor and accounting firm and considers the discharge of the independent auditor and accounting firm when circumstances warrant. Additionally, the Audit and Risk Committee is responsible for review and approval, in advance, of any and all audit and non-audit services to be performed by our independent auditor and accounting firm. The authority to pre-approve non-audit services may be delegated to one or more members of the Audit and Risk Committee. All services provided by PwC during 2022 were pre-approved by the Audit and Risk Committee.

Compensation Committee

In determining the members of the Compensation Committee, the Board considers whether directors qualify as “non-employee directors” as defined in Rule 16b-3 under the Exchange Act and as “outside directors” as defined in Section 162(m) of the Internal Revenue Code of 1986, as amended (the “Code”)

The Compensation Committee’s responsibilities include:

Compensation Committee Interlocks and Insider Participation: The directors who served as members of the Compensation Committee during 2022 were Richard B. Gaynor, M.D., Brian P. McKeon and Nancy J. Wysenski, none of whom is currently, or ever has been, an officer or employee of the Company, or had any relationship that is required to be disclosed in this proxy statement as a transaction with a related party. During 2022, none of our executive officers served as a member of the board of directors or the compensation committee (or other board committee performing equivalent functions) of any entity that had

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one or more of its executive officers serving on our Compensation Committee or our Board.

Limited Compensation Sub-Committee: The Compensation Committee has established procedures for the grant of equity awards, including grants of equity awards to eligible new employees. Effective July 2022, the Nominating and Corporate Governance Committee recommended, and the Board approved, the election of Nancy J. Wysenski as the sole member of the Limited Compensation Sub-Committee, and the Compensation Committee delegated to such sub-committee the authority to make individual grants of equity awards, up to certain specified award values, to certain newly hired employees of the Company. The Limited Compensation Sub-Committee typically grants equity awards to eligible new hires on the first Wednesday following the first Monday of each month (or the first business day thereafter if such first Wednesday is a holiday), referred to as the ‘New Hire Grant Date’, for all equity-eligible new hires who began their employment the prior month. The Limited Compensation Sub-Committee’s current approval authority is for new hire employees whose job level is below the level of Senior Vice President and for equity awards of up to $550,000 in aggregate award value per individual. New hire grants that exceed the authority of the Limited Compensation Sub-Committee must be granted by the full Compensation Committee, either on the New Hire Grant Date or as soon as practicable thereafter. All actions taken by the Limited Compensation Sub-Committee in 2022 were by written consent.

Key Contributor Award Committee: The Compensation Committee has established a Key Contributor Award Committee, consisting solely of our CEO, Richard F. Pops, and delegated to such committee the authority to make periodic grants of equity awards to employees outside of the annual and new hire equity grant cycles of the Company (such awards, “Key Contributor Awards”). The Compensation Committee also has established guidelines and procedures for grants of such Key Contributor Awards. Recipients of Key Contributor Awards are periodically selected by Mr. Pops, in consultation with other members of management and the Company’s human resources department. Key Contributor Awards are intended to reward and retain key contributors to critical Company programs. The Compensation Committee periodically reviews and confirms the Key Contributor Award Committee’s authority to continue to grant such Key Contributor Awards and the overall parameters of any proposed periodic grants of such awards, and receives detailed reports following each such grant for its review.

Financial Operating Committee

The Financial Operating Committee was formed in December 2020. The Financial Operating Committee’s responsibilities include:

In 2022, the Financial Operating Committee played an active role in the Company’s evaluation of strategic alternatives for its oncology business, and in advising Company management, and overseeing recommendations to the Board in respect of, the proposed separation of the Company’s oncology business and neuroscience business and the implementation thereof, including oversight of risks and opportunities related to such proposed separation.

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Nominating and Corporate Governance Committee

The Nominating and Corporate Governance Committee’s responsibilities include:

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Other Corporate Governance and Board Matters

Code of Business Conduct and Ethics

The Company has a Code of Business Conduct and Ethics that applies to all of the Company’s directors, employees and officers, including its principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. This Code of Business Conduct and Ethics meets the requirements of a “code of ethics” (as defined in the regulations promulgated under the Securities Act of 1933, as amended (the “Securities Act”), and the Exchange Act) and a “code of conduct” (as defined in the Nasdaq Rules). A current copy of this Code of Business Conduct and Ethics is available on the Corporate Governance page of the Investors section of our website at www.alkermes.com. We intend to disclose any amendments to our Code of Business Conduct and Ethics, or any waivers of its requirements, on our website. A copy of our Code of Business Conduct and Ethics may also be obtained, free of charge, upon request directed to: Alkermes Investor Relations, Connaught House, 1 Burlington Road, Dublin 4, Ireland, D04 C5Y6.

Members of the Board shall act at all times in accordance with the requirements of the Company’s Code of Business Conduct and Ethics, which is applicable to each director in connection with their activities relating to the Company. This obligation shall at all times include, without limitation, adherence to the Company’s policies with respect to conflicts of interest, confidentiality, protection and proper use of the Company’s assets, ethical conduct in business dealings and respect for, and compliance with, applicable law. Any request for a waiver of any of the requirements of the Code of Business Conduct and Ethics with respect to any individual director or any executive officer shall be reported to the Board and subject to its approval.

Insider Trading Policy and Hedging and Pledging Prohibitions

We maintain an Insider Trading Policy that prohibits our officers, directors, employees (including temporary employees) and independent contractors from, among other things, engaging in speculative transactions in our securities, including by way of the purchase or sale of “put” or “call” options or other derivative securities directly linked to our equity; short sales of our equity; the use of our equity as a pledge or as collateral in a margin account; and trading in straddles, equity swaps, or other hedging transactions directly linked to our equity, even if such persons do not possess material, nonpublic information. A current copy of our Insider Trading Policy is available on the Corporate Governance page of the Investors section of our website at www.alkermes.com.

Succession Planning

The Nominating and Corporate Governance Committee and the Board annually review with management the Company’s succession planning and talent assessment to ensure that the performance, development, retention and succession plans for leadership roles within the Company, including the CEO, chief financial officer, other named executive officers and current members of management, are structured to meet the short and long-term strategic objectives of the Company and support successor development and readiness. As part of this annual assessment, management also reviews with the Board the process undertaken by the Company annually, and at times more frequently, to review and assess performance, retention risk and leadership and development potential for employees of the Company at non-executive levels. This process incorporates the Company’s focus on diversity and inclusion, and includes as one of its objectives an increase in the representation of women and individuals from underrepresented communities at the Company, particularly at senior levels within the Company.

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Policies Governing Director Nominations, Evaluations and Tenure

Director Qualifications and Consideration of Diversity

The Nominating and Corporate Governance Committee is responsible for reviewing, and recommending to the Board from time to time, the appropriate background and experience, qualities, skills and expertise, and characteristics desired of Board members in the context of the then-current make-up of the Board and its alignment with the Company’s values, strategy and business needs.

This assessment includes consideration of the following minimum qualifications that the Nominating and Corporate Governance Committee believes must be met by all current directors and all individuals nominated for a director position:

The Nominating and Corporate Governance Committee also considers numerous other qualities, skills and characteristics when evaluating all current directors and individuals nominated for a director position, such as:

These factors and others are considered useful by the Board and are reviewed periodically by the Nominating and Corporate Governance Committee in the context of an assessment of the perceived needs of the Board at particular points in time. The Board has full authority to modify these criteria from time to time as it deems necessary or advisable.

Rooney Rule. When identifying potential director candidates, the Nominating and Corporate Governance Committee includes, and instructs any search firm that it engages to include a diverse slate of candidates, including candidates who are women and candidates from underrepresented communities, in any pool from which individuals are selected for nomination. In 2019, this practice, also known as a “Rooney Rule”, was codified by our Board in our Corporate Governance Guidelines.

Board Process for Evaluating and Recommending Director Nominees for Election

The Board is responsible for the nomination of directors for election to the Board. The Board delegates the evaluation and nomination of director nominees to the Nominating and Corporate Governance Committee, with the expectation that other members of the Board and management will be requested to take part in the process as appropriate. In evaluating and nominating director nominees, the Nominating and Corporate Governance Committee considers the diversity of specific experience, skills and characteristics (including, without limitation, areas of expertise, culture, age, race and ethnicity, viewpoints, tenure and gender) necessary for the optimal functioning of the Board over both the short and long term.

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Once a candidate has been identified, the Nominating and Corporate Governance Committee evaluates the candidate to confirm that the candidate meets all of the minimum director qualifications established by the Board and any additional qualifications, skills or characteristics that the Nominating and Corporate Governance Committee and the Board deems appropriate at such time and, based on the results of this evaluation, the Nominating and Corporate Governance Committee will decide whether to recommend such candidate to the Board for election. The Nominating and Corporate Governance Committee also recommends candidates for the Board’s appointment to the committees of the Board.

The Board retains the ultimate authority to recommend director nominees for election to the Board, to fill any vacancy on the Board and to appoint directors to the committees of the Board.

Procedure for Recommendations by Shareholders of Director Nominees

The Nominating and Corporate Governance Committee will consider director candidates recommended by shareholders for nomination by the Board for election at an annual general meeting of shareholders. The Nominating and Corporate Governance Committee will evaluate such recommended director candidates using the same criteria that it uses to evaluate other candidates. A shareholder who wishes to recommend individuals for consideration by the Nominating and Corporate Governance Committee and the Board may do so only by delivering a written recommendation to our Company Secretary at Alkermes plc, Connaught House, 1 Burlington Road, Dublin 4, Ireland, D04 C5Y6, Attention: Company Secretary, with the director candidate’s name, biographical information and qualifications, and a document providing evidence of the director candidate’s willingness to serve if elected.

Procedure for Nomination by Shareholders of Director Nominees

The above procedure applies to recommendations by shareholders of director candidates to be nominated by the Board. Shareholders who instead desire to nominate on their own behalf one or more persons for election to the Board at an annual general meeting of shareholders must comply with the deadlines and other requirements set forth in the Company’s Articles of Association in respect of shareholder nominations, including the applicable notice, information and consent provisions. Pursuant to our Articles of Association, nominations by our shareholders of persons for election to the Board at our 2024 annual general meeting of shareholders must be received by our Company Secretary between November 27, 2023 and January 26, 2024; provided, however, that in the event that the date of our 2024 annual general meeting of shareholders is changed by more than 30 days from the first anniversary date of the Annual Meeting, notice must be delivered no earlier than 180 days prior to, nor later than 120 days prior to, our 2024 annual general meeting of shareholders or, if later, the 10th day following the day on which public announcement of the date of our 2024 annual general meeting of shareholders is first made.

In addition to the applicable notice requirements under our Articles of Association described in the preceding paragraph, in order to comply with the SEC’s universal proxy rules, shareholders who desire to nominate one or more persons for election to the Board at our 2024 annual general meeting of shareholders must provide notice to the Company by the same deadline noted in the preceding paragraph and such notice must comply with the additional requirements of Rule 14a-19(b) under the Exchange Act.

Other Shareholder Communications with the Board

Generally, shareholders who have suggestions, comments or inquiries should contact our Investor Relations team at investor_relations@alkermes.com. However, our Board believes that shareholders should also have an opportunity to communicate with the Board directly. Shareholders interested in communicating with the Board or an individual director or directors (including the Chairman or the Lead Independent Director) may do so by sending written communication by mail to Alkermes plc, Connaught House, 1 Burlington Road, Dublin 4, Ireland, D04 C5Y6, or by facsimile to +353 1 772-8001, in each case to the attention of either the Chairman of the Board or the individual director(s), as applicable. Each communication should set forth the shareholder’s name and address as it appears on the records of our transfer agent, Computershare Trust Company, N.A. (and, if the shares are held by a bank, broker or other nominee, the name and address of the shareholder who beneficially owns of the shares), and the number of shares that are owned or beneficially owned, as applicable, by such shareholder. The Company will forward any such shareholder communications to the Chairman of the Board, as a representative of the Board, and/or to the individual director(s) to whom the communication is addressed, by certified mail to an address specified by the applicable director and/or the Chairman of the Board for such purposes or by secure electronic transmission.

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Annual Board Evaluation and Board, Committee and Individual Director Self-Assessments

As described above, our Board is tasked with, among other things, overseeing Company risk, business strategy and corporate responsibility and sustainability initiatives; fostering a company culture that attracts, retains and supports employees; engaging with shareholders and strengthening alignment with shareholder interests; and supporting long-term value creation for the Company and its stakeholders.

In order to help ensure that the current and future business and stakeholder needs of the Company are being appropriately served by the Board and its committees, the Nominating and Corporate Governance Committee:

2022 Evaluation and Assessment

Actions Taken in Response to Board Self-Assessments. Based on feedback provided by directors through this process, the Lead Independent Director of the Board worked with management to implement a number of changes to the substance and structure of regularly-scheduled Board meetings in 2022, including refining meeting agendas to add more time for discussion; increasing the scope of information provided in advance of meetings to support more focused discussion during meetings of certain topics of particular interest to the Board, including Company strategy, execution, risks and opportunities; and continuing the practice of frequent Board update calls and other communications outside of regularly-scheduled meetings.

Recent Enhancements to Board Self-Assessment Process

In 2021, the Nominating and Corporate Governance Committee worked with management to review, and substantially revise, the form of questionnaire utilized in the Board’s self-assessment process to enhance the substance and nature of the feedback solicited.  

In 2022, following review by the Nominating and Corporate Governance Committee of the Company’s Board self-assessment process in comparison to peer practices, the Nominating and Corporate Governance Committee adopted changes to the process for 2023 designed to further facilitate the sharing of candid feedback as part of the process. The 2023 Board self-assessment will be conducted by independent advisors and consist of a written instrument and individual discussions with each member of the Board. Findings from this assessment will be shared directly with the Nominating and Corporate Governance Committee.

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Board Refreshment and Tenure

The Board does not believe that establishing term limits on directors’ service or a mandatory retirement age would be in the best interests of the Company or its shareholders. Such limitations on service may result in losing the contributions of directors who, through their tenure, have developed increasing insight into the Company and its operations and provide valuable contributions to the Company, its shareholders and the Board. The Board believes that the Company and its shareholders benefit from the balance of experience and institutional knowledge of longer-serving Board members and the fresh perspectives and evolving skillsets of newer Board members.

If, as a result of the Nominating and Corporate Governance Committee’s annual evaluation of the composition and effectiveness of the Board and/or the Board’s annual self-assessment process, the Board identifies specific qualifications, attributes or areas of expertise that may be additive to the Board in light of the Company’s evolving business strategy and areas of focus, the Board may identify, or engage an external recruitment firm to identify, new director candidates with experience and expertise in the identified areas.

Ongoing Board Refreshment: 2019—Present: The Board has an active Board refreshment program and has engaged in significant Board refreshment activities since 2019 in order to further strengthen the Board’s expertise in targeted areas of importance to the Company’s business strategy. As part of these refreshment activities, the average tenure of our Board members has decreased significantly since 2019.

Details of the Board’s refreshment activities and changes to average tenure since 2019 are as follows:

The following new, independent directors have been added to the Board since 2019:

Focus on diversity in director candidate searches: The Board recognizes the immense value of a diverse and inclusive membership that includes not only diversity of qualifications, tenure, viewpoints and professional background, but also diversity of age, gender, race and ethnicity, and recognizes the importance of setting an example at the Board level for the diverse and inclusive culture and talent that the Company seeks to foster and attract. As the Board has engaged in active refreshment efforts, it seeks to identify new director candidates who can further contribute to the diversity of the Board.

As a result of these refreshment activities and our commitment to Board diversity, our Board and Board committees have a strong representation of diverse directors:

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Expectations of Board Members

Director Orientation and Continuing Education

The Board believes that each director should be aware of corporate governance issues, legal duties and obligations and best practices involved in serving on a public company board of directors. The Company’s Chief Legal Officer and Chief Financial Officer are responsible for the orientation and onboarding of new directors, and for periodically providing materials or briefing sessions for directors on subjects that may assist them in exercising their duties. The Company also provides frequent opportunities for the Board or individual directors to engage with team leaders in different functional areas of the Company and visit Company facilities in order to support greater understanding of the Company’s business, strategy and operations.

The Nominating and Corporate Governance Committee considers potential continuing education topics for the Board and provides recommendations to the Board as it deems appropriate. From time to time, external advisors are invited to present to, and discuss with, the Board or a delegated subset of the Board, developments in corporate governance best practices, changes in regulations applicable to the Company and significant changes in institutional investor sentiment and/or proxy advisory firm policies.

Service on Other Boards

Board members are expected to ensure that their existing and planned future commitments do not materially interfere with their service as an effective member of our Board. Any existing outside commitments of Board members are considered by the Nominating and Corporate Governance Committee and the Board when reviewing new director candidates and current director candidates for nomination for election to the Board. In addition, Board members must seek approval from the Nominating and Corporate Governance Committee before accepting an invitation to serve on any new board of directors, and service on boards and board committees of other companies must be consistent with the Company’s conflict of interest policies set forth in our Code of Business Conduct and Ethics.

Overboarding Policy. In May 2022, the Board revised its policy regarding directorships to further limit the number of public company boards on which our directors may serve. In accordance with the revised policy, unless otherwise agreed by the Nominating and Corporate Governance Committee, our directors may serve on public company boards as follows:

In calculating the number of public company boards on which a director serves, simultaneous service on a board or committee of a public company parent and its substantially owned non-public subsidiary counts as service on a single public company board or committee. Each member of our Board is currently, and was at all times during 2022, in compliance with our overboarding policy.

Meetings of the Board

Meetings of the Board are scheduled in advance at least four times a year. Furthermore, additional Board meetings may be called upon appropriate notice at any time to address specific needs of the Company or as requested by the Board. Each director may propose the inclusion of items on the agenda, request the presence of, or a report by, any member of Company management, or at any Board meeting raise subjects that are not on the agenda for that meeting. The Lead Independent Director reviews and approves the agenda in advance of each Board meeting. The meetings of the Board are typically hosted at the Company’s headquarters in Dublin, Ireland, but may be hosted at other locations or conducted by audio or video conference at the discretion of the Board. In 2022, one regularly-scheduled meeting of the Board was conducted via videoconference rather than in-person in light of COVID-19-related considerations.

Attendance at Board and Committee Meetings

Absent extenuating circumstances, directors are expected to prepare for, attend and participate in all Board meetings and meetings of the committees on which they serve. Attendance rates are taken into account by the Nominating and Corporate Governance Committee and the Board in connection with their assessments of current Board members for re-nomination as directors.

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In 2022, each of the Company’s directors attended more than 75% in the aggregate of all regularly-scheduled meetings of the Board and the committee(s) on which they served held during the period in which they were a director or committee member, as applicable.

Frequency and Format of Board Meetings

We held four regularly-scheduled meetings of the Board during 2022. In addition, in recognition of evolving demands on the Company and the Board’s oversight of such demands and other matters of importance to the Company, we also held numerous (at least monthly, and more frequently as needed) Board update calls in 2022 to keep the Board informed, engaged and in regular communication with management.

Meetings of Non-Employee Directors

The Board’s policy is to hold meetings of the non-employee directors of the Board (currently consisting of all directors other than Mr. Pops) following each regularly scheduled in-person Board meeting. The Lead Independent Director is responsible for chairing such meetings. Meetings of the non-employee directors were held following each regularly-scheduled Board meeting during 2022. At times when the non-employee directors include any directors who are not independent, the Board shall also hold executive sessions of the independent directors of the Board from time to time, as the Board deems appropriate.

Action by Written Consent

In accordance with our Articles of Association, the Board may, from time to time, take action by unanimous written consent in lieu of a meeting. The Board did not take any actions by written consent in 2022.

Attendance at Annual General Meetings of Shareholders

All directors and director nominees are encouraged to attend the Company’s annual general meetings of shareholders, and ten of the Company’s then-current directors attended the Company’s 2022 annual general meeting of shareholders.

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Director Compensation

Directors who are employees of the Company do not receive additional compensation for Board membership over and above their regular employee compensation.

Non-Employee Director Compensation Program

Our non-employee director compensation program is intended to be current, competitive and fair, and is designed to attract and retain optimal talent and expertise on our Board and provide compensation commensurate with the time and effort that our directors are required to devote to the Company given the size and complexity of our operations and the Board’s significant oversight and advisory responsibilities.

The Compensation Committee is responsible for evaluating and recommending to the Board for its approval an annual non-employee director compensation program. In this context, the Compensation Committee annually reviews and evaluates, in consultation with its independent compensation consultant, recent trends in director compensation, related corporate governance best practices, and comparable market data, including data from the same peer group that the Compensation Committee uses for executive compensation purposes. The Compensation Committee makes its recommendations for non-employee director compensation to the Board based on such review and evaluation. The Board retains the ultimate authority to determine the form and amount of director compensation.

It is the general philosophy of the Board that non-employee director compensation should be a mix of cash and equity-based compensation. No perquisites are provided to our non-employee directors. For purposes of our director compensation program, unless otherwise noted below, each “year” refers to the approximately 12-month period between our annual general meetings of shareholders.

Annual Cash Retainers

Each non-employee director receives an annual cash retainer for their service on the Board and an additional annual cash retainer if they serve as Lead Independent Director of the Board or as a member or chair of a standing committee of the Board or the Financial Operating Committee. Each non-employee director also receives an additional fee for attendance at each regularly-scheduled meeting of the Board in excess of a pre-determined number of meetings each year as set forth below. 

No changes to existing retainers. In May 2022, following review of the non-employee director annual cash retainers approved in May 2021, and determination that such cash compensation remained aligned, and competitive, with the Company’s peer group, the Compensation Committee recommended to the Board that no changes be made in 2022 to any existing annual cash retainer fee amounts. The Board subsequently approved this recommendation, resulting in the following annual retainers for non-employee directors’ leadership and service roles on the Board and its committees for the coming year, each paid pro-rata on a quarterly basis:

*This amount includes compensation for attendance at the first five regularly-scheduled Board meetings held each year. An additional fee of $3,500 is paid to each non-employee director for their attendance at any regularly-scheduled Board meeting in excess of the fifth regularly-scheduled Board meeting occurring in such year.

In 2022, in recognition of continuing and evolving demands on the Company, and the Board’s oversight of such demands and other matters of importance to the Company, we conducted numerous Board update calls to keep the Board informed, engaged and in regular communication with management. None of the directors received any additional compensation for their participation in such calls.

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Equity Compensation

Each non-employee director is also granted equity for their Board service, in the form of an annual award (the “Annual Grant”) that is typically granted to all continuing non-employee directors each year on the date of the Company’s annual general meeting of shareholders, following the election of directors at such meeting. Any newly appointed non-employee director who joins the Board after the annual general meeting of shareholders is granted a prorated portion of the Annual Grant, typically granted to such director proximate to the date of such director’s election to the Board, with the value of the award prorated based on the number of days remaining until the one year anniversary of the Company’s prior annual general meeting of shareholders, divided by 365 (each such grant, a “Pro-Rata Annual Grant”). In addition, each newly appointed non-employee director is granted an initial award for joining the Board (each, a “New Director Grant”), typically granted to such director proximate to the date of such director’s election to the Board, with the award value equal to 1.5 times the approved award value of the Annual Grant.

Vesting terms. Per our non-employee director equity grant procedures, Annual Grants and Pro-Rata Annual Grants vest in full on the one-year anniversary of the applicable grant date, and New Director Grants vest in three equal annual installments, commencing on the one-year anniversary of the applicable grant date.

No changes to award values in 2022. Each year, prior to the Company’s annual general meeting of shareholders, the Compensation Committee recommends to the Board for its approval equity award values and terms for the Annual Grant and any New Director Grant for the coming year. In May 2022, following review of the target equity compensation value of $375,000 for the Annual Grant and $562,500 for the New Director Grant approved in 2021, and determination that such equity compensation values remained aligned to and competitive with the Company’s peer group, the Compensation Committee recommended to the Board that no changes be made to the non-employee director equity award values for the coming year and the Board subsequently approved this recommendation.

Equity mix and share number calculation methodology. All grants to our non-employee directors in 2022 consisted of 50% restricted stock unit awards and 50% stock options, with the number of shares underlying each restricted stock unit award calculated by dividing the approved aggregate value of such awards by the closing price of the Company’s ordinary shares on the Nasdaq Global Select Market as of the close of trading on the applicable grant date (the “Grant Date Closing Share Price”), and the number of shares underlying each stock option calculated utilizing the Grant Date Closing Share Price and the Black-Scholes valuation model, in each case with the resulting share number rounded up to the nearest whole number of shares.

Our non-employee directors are not granted any equity other than the Annual Grant (or Pro-Rata Annual Grant, as applicable) each year and a one-time New Director Grant upon joining the Board. For a description of our share ownership and holding guidelines applicable to our directors, see the section entitled “Share Ownership and Holding Guidelines” on page 115 of this proxy statement.

Reimbursement of Expenses and Insurance

We reimburse each non-employee director for necessary business expenses incurred in the performance of their Board service and extend coverage to each non-employee director under our travel accident and directors’ and officers’ indemnity insurance policies.

Conflicts of Interest

Independent directors do not receive consulting, advisory or other compensatory fees from the Company if the receipt of such fees would result in disqualifying the director from being considered an “independent” director in accordance with the applicable provisions of the Nasdaq Rules and the Exchange Act and the rules promulgated thereunder. To the extent practicable or required by applicable rule or regulation, independent directors who are affiliated with the Company’s service providers, partners or collaborators will undertake to ensure that their compensation from such providers, partners or collaborators does not include amounts connected to payments by the Company.

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2022 Director Compensation Table

Each of Emily Peterson Alva, Shane M. Cooke, David A. Daglio, Jr., Richard B. Gaynor, M.D., Cato T. Laurencin, M.D., Ph.D., Brian P. McKeon, Nancy L. Snyderman, M.D., Frank Anders Wilson and Nancy J. Wysenski served as non-employee directors during all of 2022. David W. Anstice AO and Wendy L. Dixon, Ph.D. served as non-employee directors in 2022 until their retirement from the Board at the close of the 2022 Annual Meeting. Christopher I. Wright, M.D., Ph.D., was appointed to the Board on May 24, 2022 and served as a non-employee director from such date through the end of 2022.

Richard F. Pops, our CEO and Chairman of the Board, was an employee during all of 2022. As an employee, Mr. Pops does not receive any cash or equity compensation for his service on the Board.

The following table presents and summarizes the cash retainer fee amounts earned or paid to our non-employee directors for service during 2022 and the equity compensation granted to our non-employee directors in 2022:

*Numbers may not sum due to rounding.

Notes to 2022 Director Compensation Table

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Corporate Responsibility and Sustainability

We are committed to operating and growing our business in a sustainable and responsible manner, including in respect of our ESG impacts, and in a manner that promotes transparent governance and strong ethics.

Our most recent Corporate Responsibility Report, published in September 2022, highlights:

The report is available on the Responsibility section of our website at www.alkermes.com.

We actively engage with our stakeholders, including our shareholders, employees, customers, vendors, patients and caregivers, policy makers and members of our local communities, in order to understand the ESG matters of interest to them, guide our advocacy efforts and help inform our approach to the development and commercialization of our medicines. Feedback received from our stakeholders is communicated to our management team, the full Board and committees of the Board, as appropriate.

Human Capital Management

Our employees are the foundation upon which our business is built. As of the Record Date, we had approximately 2,255 full-time employees, of which approximately 1,840 were based in the U.S. and approximately 415 were based in Ireland.

Corporate Culture and Employee Development

Employee Engagement

We encourage active employee engagement to help ensure that employees feel part of our mission and that they have a voice in the Alkermes community. Since 2017, we have conducted periodic engagement surveys to understand employee sentiment regarding, and satisfaction with, their work and experience. We have used, and plan to continue to use, the data collected to help inform and evolve our human capital management strategy and initiatives. In 2022, we also implemented function- and site-specific mentoring programs and conducted open forums with leaders, among other company events.

Following the emergence of COVID-19, we adapted our remote work and virtual engagement policies to allow more flexibility to our employees. As many of our employees continued to work remotely in 2022, employee engagement remained a top priority for the Company. We continued to establish virtual touchpoints through global employee town halls and other communication channels and enhanced our technologies and communication strategies in order to keep employees feeling connected, motivated, supported and informed.

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Diversity, Inclusion & Belonging (“DIB”)

In support of this strategy, in 2019, we created a global, cross-functional DIB Steering Committee, comprised of representatives from all of our locations, including field-based employees, to create connections, foster conversations, help ensure our efforts are aligned with the diverse range of perspectives within our organization and develop and advance practices, tools and resources that can be used to strengthen the sense of belonging among our employees.

Since 2020, we have launched five Employee Resource Groups (“ERGs”): Limitless, a network to support people impacted by disabilities or illness; Mosaic, a multicultural network; Operation Salute, a veterans’ network; Pride@Work, an LGBTQ+ and allies network; and Women Inspired Network (WIN), a women’s network. Participation in our ERGs is voluntary and open to all employees. These ERGs share a common purpose of supporting and enhancing the inclusiveness of our company culture and providing opportunities for professional development, networking and building deeper connections within Alkermes.

In 2021, we established a DIB Executive Committee, which includes our CEO and other senior leaders, that meets quarterly to refine our DIB strategy and champion its implementation and impact across the business. Our DIB committees work with our ERGs to set goals, establish and execute strategic initiatives, measure our progress and promote a culture of understanding and inclusion throughout our business. In 2022, members of our ERGs worked alongside our Human Resources team to enhance our benefits and human resources policies to support recruitment and retention of diverse talent.

In addition, as part of our increased focus on social and racial justice, diversity and inclusion, and in response to global events throughout the last few years, we held company-wide town hall conversations, sponsored recognition events, supported non-profit organizations committed to diversity and enhanced our Company’s diversity education and training. In 2022, we held more than 18 DIB-related education, awareness and training programs with aggregate attendance of approximately 2,800 employees from across the organization. We also created a DIB goal for senior leaders that was incorporated into their respective individual 2022 performance objectives.

Health, Safety and Wellness

We ask our employees to help us promote and sustain workplace environments that are safe, productive and protective of the health and well-being of our people and in compliance with applicable laws, rules and regulations. We maintain extensive Environment, Health, Safety and Security (“EHSS”) corporate policies, adhere to all health and safety standards set by regulators in the locations in which we operate, and routinely assess workplace risks, conduct employee trainings and monitor our sites to reduce the risk of workplace accidents. These efforts contributed to our ability to maintain rates of workplace accidents resulting in recordable injuries, and of accidents resulting in lost employee work time, below U.S. Bureau of Labor Statistics industry averages in 2022.

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We are proud to have received external recognition for our employee health, safety and well-being programs. In 2020, our recently-built site in Waltham, Massachusetts was awarded a three-year Fitwel^® certification in 2020 in recognition of its facility design intended to foster a healthy and productive workplace. In 2022, our sites in Ireland were recertified to the Irish Business Employers Confederation (IBEC)’s KeepWell Mark™, an evidence-based workplace well-being accreditation awarded to companies who meet or exceed industry standards for well-being, health and safety, and Alkermes was included in the IBEC’s listing of Ireland’s Leading in Wellbeing Top 100 Companies 2022, which recognizes companies that have implemented well-being best practices for employees and local business communities.

Environmental Impact and Sustainability

At Alkermes, our goal is to conduct our business activities in a manner that minimizes the environmental impacts of our operations and promotes effective stewardship of environmental resources. We are committed to complying with applicable laws, rules and regulations and operating with the highest standards of conduct. All Alkermes facilities are subject to routine regulatory inspections, including in respect of EHSS, to confirm compliance with applicable laws and regulations. We work collaboratively across stakeholder groups and business units throughout the organization to identify ways to reduce our environmental impact, mitigate EHSS risk and increase operational efficiencies. These efforts and our environmental performance metrics are discussed in detail in our Corporate Responsibility Report. As a testament to these efforts, in 2021, our manufacturing facility in Athlone, Ireland successfully completed certification to the Business Working Responsibly Mark, an independently audited standard for corporate social responsibility and sustainability based on ISO26000.

In recent years, we further strengthened our governance related to environmental sustainability matters through the establishment of cross-functional steering teams and oversight committees tasked with development and implementation of our environmental sustainability strategy. In support of this strategy, in 2022, we engaged two third-party environmental service providers to support our efforts to enhance our environmental performance and our measurement and reporting of such performance, to assess potential for future goal-setting or other initiatives, and to refine our environmental sustainability risk assessments and mitigations.

Product Quality and Patient Safety

Across our business, we maintain an unwavering focus on product quality and safety. All Alkermes facilities are subject to routine regulatory inspections in respect of product quality and safety to confirm compliance with applicable laws and regulations. We have robust policies and procedures in place designed to promote safe and sustainable research, development, manufacture and commercialization of products, including a comprehensive quality management system that is designed to ensure that products we manufacture, store, test or distribute consistently meet applicable product specifications, safety and efficacy standards, “good practice” GxP quality guidelines and regulations (e.g., GCP, GMP, GLP) and other regulatory requirements.

We are committed to ensuring the authenticity of our medicines and guarding against counterfeit products (those not equivalent in quality, safety and efficacy, or not containing the correct amount of active ingredient and/or containing impurities) in the marketplace. We have standard operating procedures for the timely and efficient removal from the market of any commercial drug product suspected or found to not meet our product quality or patient safety standards, which include notification of and consultation with applicable regulatory authorities, conduct of a health hazard assessment, and communications to customers, partners, healthcare providers and patients as directed by regulators or our internal policies.

Responsibility in Manufacturing and Supply Chain

We are committed to meeting our manufacturing objectives reliably and responsibly through the establishment and maintenance of a safe, sustainable and ethical supply chain. We contract with a growing network of third-party manufacturers to formulate certain products and produce components of products or product packaging for clinical and commercial use. All service providers involved in the manufacture and packaging of our products are subject to inspection by the FDA or comparable agencies in other jurisdictions and we require that our contract manufacturers adhere to current Good Manufacturing Practices (“GMP”) in the manufacture of these products and product components. All contract manufacturers and suppliers must undergo a pre-approval inspection by our quality personnel to assess their compliance with applicable standards and regulations prior to initiating work for Alkermes.

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Social Responsibility and Community Impact

We also support research and advocacy efforts to raise awareness of patient needs and to increase access to medicines and other forms of treatment in support of patient health and well-being. We proudly support not-for-profit organizations and independent researchers working in our therapeutic areas of focus through our two grant programs:

Early Access Policy

We endeavor to make safe and effective medicines by conducting rigorous clinical trials and obtaining marketing approval from regulatory authorities, including the FDA. Participation in one of our clinical trials is the optimal way for patients to gain access to our investigational medicines prior to regulatory approval. However, we understand that some patients may not be able to participate in a clinical trial. If early data from our clinical trials suggest that an investigational treatment might offer benefits for patients facing serious or life-threatening conditions, we have a policy under which patients may be eligible to receive access to an investigational medicine outside the context of a clinical trial. Additional details, including eligibility criteria, can be found in the Alkermes Early Access Policy, a copy of which is available on the Early Access page of the Research and Development section of our website at www.alkermes.com.

Patient Advocacy and Community Engagement

Patient advocacy and community engagement are core to our mission. We are inspired by the courage of individuals who face the challenges of living with addiction, serious mental illness and cancer, and the perspectives of those affected by these conditions are paramount to our work. We regularly engage with these individuals and their caretakers, and with policymakers and leaders in the patient advocacy community, to better understand their perspectives and goals and the complex system of care for these diseases. Learnings from these interactions help to inform our business activities, including design of our clinical development and lifecycle management programs for our investigational and marketed medicines with specific patient outcomes in mind, and the nature and substance of our policy and advocacy efforts.

Our Response to COVID-19

Since the emergence of the COVID-19 pandemic, our main priorities have been, and continue to be, to protect the safety and health of our employees and to help ensure the supply of, and access to, our development products for people enrolled in our clinical studies and marketed products for people living with opioid dependence, alcohol dependence, schizophrenia and bipolar I disorder.

We have adapted our business practices in innovative ways to continue to operate safely and reliably and, in doing so, meet our public health responsibilities, which have become even more pronounced during this challenging time. We expanded our injection site network to include additional appropriate retail pharmacies and clinics where patients could receive injections of our proprietary medicines ARISTADA, ARISTADA INITIO^® and VIVITROL, and increased our disease state education and awareness efforts, including through social media platforms and unbranded disease state education campaigns. For our ongoing clinical trials, we worked closely with clinical trial sites to support continuity of care.

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PROPOSAL 2

NON-BINDING ADVISORY VOTE ON THE COMPENSATION OF THE COMPANY’S NAMED EXECUTIVE OFFICERS

(Ordinary resolution)

Our Compensation Discussion and Analysis, which begins on page 91 of this proxy statement, describes our executive compensation program and the compensation decisions that the Compensation Committee made with respect to the compensation of our named executive officers for 2022. This vote is not intended to address any specific item of compensation, but rather the overall compensation of our named executive officers and the philosophy, policies and practices described in this proxy statement. As required pursuant to Section 14A of the Exchange Act, our Board is asking that our shareholders cast a non-binding, advisory vote FOR the following resolution:

“RESOLVED, that the Company’s shareholders approve, on a non-binding, advisory basis, the compensation paid to the Company’s named executive officers, as disclosed in this proxy statement pursuant to Item 402 of Regulation S-K, including the Compensation Discussion and Analysis, and related compensation tables and narrative discussion.”

Non-Binding, Advisory Vote. Our Board is asking that shareholders support this Proposal 2. This proposal is advisory and non-binding; as an ordinary resolution, approval of this proposal requires the affirmative vote of a majority of the votes cast by shareholders on the resolution in person or by proxy. Although the vote you are being asked to cast is advisory, and therefore non-binding, we value the views of our shareholders, and the Compensation Committee will consider the outcome of the vote when designing our future compensation programs and making future compensation decisions for our named executive officers. Abstentions and broker non-votes will not have any effect on the results of those deliberations because they are not considered to be votes cast.

Say-on-Pay – 2021 Executive Compensation. At our 2022 Annual Meeting, our say-on-pay proposal related to our 2021 executive compensation program received support of approximately 86% of the votes cast. We believe this support reflects the meaningful changes that our Compensation Committee has made to our executive compensation programs since 2020 in response to shareholder feedback. The 86% support level reflects an “against” vote from one of our larger shareholders (representing approximately 10% of the votes cast on the 2022 proposal) who, throughout numerous engagements with the Company and members of our Board, did not express any specific concerns with our executive compensation practices or our 2021 executive compensation program.

At our 2018 annual general meeting of shareholders, over 99% of the votes cast by our shareholders supported holding an advisory vote on our executive compensation on an annual basis. In light of this vote, and consistent with the prior recommendation of the Board, we intend to continue to hold non-binding advisory votes on executive compensation on an annual basis, until the next required advisory vote on the frequency of such votes, which will occur at our 2024 annual general meeting of shareholders.

2022 Continued Engagement and Board Responsiveness. Throughout 2022, we continued to actively engage with our shareholders on a regular basis to solicit their feedback regarding our executive compensation programs, our governance practices and other matters of interest to our shareholders. We requested engagement meetings with shareholders who collectively held approximately 60% of our outstanding shares and held meetings with shareholders who collectively held approximately 55% of our outstanding shares. Our Lead Independent Director and other members of our Board participated in certain of these meetings alongside representatives of management. During these engagements, shareholders generally acknowledged the Board and Compensation Committee’s responsiveness to shareholder feedback and the significant enhancements to our executive compensation programs in recent years.

Enhancements to Executive Compensation Program. We have made meaningful enhancements to our executive compensation program since 2020, including in 2022, to further align the interests of our CEO and other named executive officers with those of our shareholders. For additional information, see “Board Responsiveness—Enhancements to Compensation Practice” beginning on page 93 of this proxy statement.

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PROPOSAL 3

NON-BINDING RATIFICATION OF APPOINTMENT OF INDEPENDENT AUDITOR

AND ACCOUNTING FIRM AND BINDING AUTHORIZATION OF AUDIT AND RISK COMMITTEE

TO SET INDEPENDENT AUDITOR AND ACCOUNTING FIRM’S REMUNERATION

(Ordinary resolution)

PwC served as our independent auditor and accounting firm for 2022. The Audit and Risk Committee reviewed and discussed the performance of PwC as the Company’s independent auditor and accounting firm for 2022 and, following such review and discussion, has retained PwC to serve as the Company’s independent auditor and accounting firm for 2023. Although we are not required to submit the appointment of PwC for shareholder approval, as a matter of good corporate governance, the Board has determined, upon the recommendation of the Audit and Risk Committee, to submit the selection of PwC for ratification by the Company’s shareholders and to ask that the Company’s shareholders authorize the Audit and Risk Committee to set the independent auditor and accounting firm’s remuneration. Even if the selection of PwC is ratified, the Audit and Risk Committee, in its discretion, may still select a different independent auditor and independent accounting firm at any time during the year if it determines that such a change would be in the best interests of the Company and its shareholders.

Majority Voting Standard. The resolution in respect of the authorization component of this Proposal 3 is an ordinary resolution that requires the affirmative vote of the majority of the votes cast on the resolution in person or by proxy (meaning the number of shares voted “FOR” this Proposal 3 must exceed the number of shares voted “AGAINST” this Proposal 3). Abstentions and broker non-votes (if any) will have no effect on the outcome of this Proposal 3 because they are not considered to be votes cast.

A representative of PwC is expected to attend the Annual Meeting. Such representative will be given an opportunity to make a statement if they so desire and will be available to respond to appropriate questions.

The text of the resolution in respect of this Proposal 3 is as follows:

“RESOLVED, to ratify, on a non-binding, advisory basis, the appointment of PricewaterhouseCoopers LLP as the independent auditor and accounting firm of Alkermes plc and to authorize, in a binding vote, the Audit and Risk Committee to set the independent auditor and accounting firm’s remuneration.”

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PROPOSAL 4

APPROVAL OF

ALKERMES PLC 2018 STOCK OPTION AND INCENTIVE PLAN, AS AMENDED

(Ordinary resolution)

Overview

Our Board is requesting shareholder approval of the Alkermes plc 2018 Stock Option and Incentive Plan, as amended (the “2018 Plan”), as proposed to be further amended in accordance with this Proposal 4, to make the following material changes:

The 2018 Plan, as proposed to be amended in accordance with this Proposal 4, is attached as Appendix A to this proxy statement and is incorporated herein by reference. For purposes of this Proposal 4, we refer to the 2018 Plan, as proposed to be amended in accordance with this Proposal 4, as the “Amended 2018 Plan.”

If this Proposal 4 is approved by our shareholders, the Amended 2018 Plan will become effective as of the date of the Annual Meeting. In the event our shareholders do not approve this Proposal 4, the Amended 2018 Plan will not become effective and the 2018 Plan will continue to be effective in accordance with its terms.

Why do we believe our shareholders should approve the Amended 2018 Plan (including the increased number of shares authorized for issuance thereunder)?

1. We believe the size of our share reserve increase request is reasonable.

The size of our share reserve increase request for the Amended 2018 Plan is equal to 6,500,000 new ordinary shares (subject to adjustment for stock splits, stock dividends and similar events). We expect our request will provide us with sufficient ordinary shares to support approximately one to two years of equity awards at our current market value. Equity awards are key to our ability to attract, retain and incentivize employees who are integral to the successful development of our pipeline candidates, the commercialization of our products and the accomplishment of transformative business transactions. Our compensation philosophy with respect to equity awards is to target around the 50^th percentile by value of our comparable peer group, as determined using the Black-Scholes option pricing model for stock options and market prices for restricted stock unit awards, with the opportunity to increase or decrease the value of equity awards from the 50^th percentile based upon individual performance and other factors. If our request is not approved, we do not expect to have sufficient ordinary shares to support our next round of annual equity awards at our current market value.

2. Equity awards are integral to our compensation program and to our success.

Equity awards, similar to those typically offered by our competitors, have been, and we believe will continue to be, an integral component of our overall compensation program, enabling us to attract qualified and skilled employees and directors, retain our existing employees, including our experienced management team, and provide incentives for our employees to exert maximum efforts for our success, ultimately contributing to the creation of shareholder value.

We have built, and continue to devote significant resources to further develop and enhance, a comprehensive cross-functional infrastructure designed to support product development from discovery through commercialization and lifecycle management. We have a portfolio of proprietary products that we manufacture, market and sell in the U.S. and we are currently developing a pipeline of potential new proprietary products. We also manufacture commercial products that incorporate our proprietary technologies

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under license that are owned and commercialized by other biopharmaceutical companies and for which we receive manufacturing and/or royalty revenues.

We seek to attract, hire, develop, retain and motivate qualified and highly-skilled personnel with experience in areas such as R&D, including early discovery, translational medicine, formulation and clinical development capabilities; intellectual property prosecution, enforcement and defense; medical affairs; manufacturing operations; U.S. federal and state government affairs; sales and marketing; and market access, among other areas. Competition for such personnel in our industry and the geographic regions in which we operate is intense, with numerous companies also developing, launching or marketing products, including products against which our products directly compete.

3. We manage our equity award use carefully.

We carefully and thoughtfully manage our equity award use, balancing attraction, retention and incentivization of our employees against dilution and burn rate considerations. As of the Record Date, our full dilution, which is calculated as (shares available for grant + shares subject to outstanding equity awards) / (shares outstanding + shares available for grant + shares subject to outstanding equity awards), is approximately 17.3%.

The following two tables provide certain additional information regarding our equity incentive program and include awards granted under all of our equity incentive plans.

The following table sets forth our historic use of equity in 2022, 2021 and 2020:  

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Important Aspects of the Amended 2018 Plan Designed to Protect our Shareholders’ Interests

The Amended 2018 Plan contains certain provisions, including those set forth below, designed to protect our shareholders’ interests and to reflect corporate governance best practices. The descriptions of these provisions and of certain other features of the Amended 2018 Plan contained in this Proposal 4 are intended to be summaries only and are qualified in their entirety by the full text of the Amended 2018 Plan attached hereto as Appendix A.

Majority Voting Standard

The resolution in respect of this Proposal 4 is an ordinary resolution that requires the affirmative vote of the majority of the votes cast on the resolution in person or by proxy (meaning the number of shares voted “FOR” this Proposal 4 must exceed the number of shares voted “AGAINST” this Proposal 4). Abstentions and broker non-votes will have no effect on the outcome of this Proposal 4 because they are not considered to be votes cast.

The text of the resolution in respect of this Proposal 4 is as follows:

“RESOLVED, that the Alkermes plc 2018 Stock Option and Incentive Plan, as amended, be APPROVED.”

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Principal Features of the Amended 2018 Plan

The material features of the Amended 2018 Plan are as described below. These descriptions are intended to be summaries only and are qualified in their entirety by the full text of the Amended 2018 Plan attached hereto as Appendix A.

The maximum number of ordinary shares that may be issued under the Amended 2018 Plan is equal to the sum of the following (subject to adjustment for stock splits, stock dividends and similar events): (i) 42,400,000 ordinary shares; (ii) 1,199,965 ordinary shares, which is the number of 2011 Plan Available Shares (as defined in the 2018 Amended Plan and described below); and (iii) the Prior Plans Returning Shares, as such shares become available from time to time. For purposes of this limitation, shares underlying any awards granted under the Amended 2018 Plan that are forfeited, canceled, repurchased or otherwise terminated (other than by exercise) will be added back to the number of shares available for issuance under the Amended 2018 Plan. Shares tendered or held back upon exercise of an option or stock appreciation right or settlement of an award to cover the exercise price or tax withholding for such option, right or award are not added back to the number of shares available for issuance under the Amended 2018 Plan. Shares purchased in the open market with proceeds from the exercise of options or stock appreciation rights will not be added to the number of shares available for issuance under the Amended 2018 Plan. In addition, in the event that a stock appreciation right is settled in shares, the gross number of shares subject to the stock appreciation right will be deducted from the number of shares available for issuance under the Amended 2018 Plan. The shares

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issued under the Amended 2018 Plan may be issued from treasury or otherwise.

The term “2011 Plan Available Shares” generally means the 1,199,965 ordinary shares that remained available for grant under the 2011 Plan as of May 20, 2020 (the date of the Company’s 2020 annual general meeting of shareholders), which ordinary shares ceased to be available for grant under the 2011 Plan (and became available for issuance pursuant to Awards under the 2018 Plan) as of such date.

Summary of the Amended 2018 Plan

Plan Administration.  The Administrator has full power to select, from among the individuals eligible for awards, the individuals to whom awards will be granted, to make any combination of awards to participants, and to determine the specific terms and conditions of each award, subject to the provisions of the Amended 2018 Plan. The Administrator may also determine and modify the terms and conditions, including restrictions, not inconsistent with the terms of the Amended 2018 Plan, of any award and accelerate the exercisability or vesting of all or any portion of any award, except that within the minimum vesting periods described below, vesting may be accelerated only in the case of a grantee’s death, disability or retirement or upon a Sale Event (as defined in the Amended 2018 Plan). Subject to applicable law, the Administrator may also delegate to a subcommittee comprised of one or more members of the Board all or part of the Administrator’s authority and duties with respect to the granting of awards to employees who are not subject to the reporting and other provisions of Section 16 of the Exchange Act. Any such delegation by the Administrator shall include a limitation as to the amount of awards that may be granted during the period of the delegation and shall contain guidelines as to the determination of the exercise price, if applicable, and the vesting criteria.

Eligibility and Limitations on Grants.  Persons eligible to participate in the Amended 2018 Plan will be those officers, employees, non-employee directors and consultants of the Company and its subsidiaries as selected from time to time by the Administrator. The intention in making awards to eligible persons under the Amended 2018 Plan will be to align the compensation of these individuals over a multi-year period directly with the interests of our shareholders and serve as a tool in the recruitment and retention of these individuals. As of the Record Date, we (including our subsidiaries) had approximately 2,255 employees (including officers), 10 non-employee directors, and approximately 600 consultants. The maximum number of ordinary shares that can be awarded in the form of incentive stock options under the Amended 2018 Plan will not exceed 52,400,000 shares (subject to adjustment for stock splits, stock dividends and similar events).