This Proxy Statement and the accompanying BLUE Proxy Card are being furnished to shareholders (“Shareholders”) of Amarin Corporation plc (“Amarin” or the “Company”) in connection with the solicitation of proxies by Sarissa Capital Management LP, a Delaware limited partnership (“Sarissa Capital”), and the other Participants (as hereinafter defined), to be used at the general meeting of Shareholders (the “General Meeting”) which is scheduled to be held at the Dublin offices of Arthur Cox LLP, Ten Earlsfort Terrace, Dublin 2, D02 T380, Ireland, on February 28, 2023 at 3:00 p.m. local time, and at any adjournments, postponements or continuations thereof. This Proxy Statement and the BLUE Proxy Card are first being furnished to Shareholders on or about [•], 2023.

The Board of Directors of Amarin (the “Board”) currently consists of nine directors. Pursuant to Amarin’s Articles of Association (as may be subsequently amended or restated, the “Articles”), the Board shall be comprised of not more than fifteen directors, and the Board may appoint additional directors so long as the total number of directors does not exceed the maximum number fixed in accordance with the Articles. Pursuant to the Articles, directors may be removed and replaced by ordinary resolution of the Shareholders.

At the General Meeting, the Participants will seek to remove Mr. Wold-Olsen from office as a director of the Company.

The following is the text of the proposed resolution:

“THAT Per Wold-Olsen be removed from office as a director of the Company with immediate effect.”

The Participants are bringing Proposal 1 for consideration at the general meeting because, under the watch of Mr. Wold-Olsen, as Chairman, the Company has lost significant shareholder value, failed to deliver on business objectives communicated to shareholders, and failed to advance shareholder representation on the Board and so as to have enough open seats of the Board to seat the Nominees (as defined below).

On January 10, 2023, Sarissa Capital Catapult Fund LLC, a Delaware limited liability company (“Catapult”), Sarissa Capital Hawkeye Fund LP, a Delaware limited partnership (“Hawkeye”), ISP Fund LP, a Delaware limited partnership (“ISP”), Sarissa Capital Offshore Master Fund LP, a Cayman Islands exempted limited partnership (“Offshore”), Sarissa Capital Master Fund II LP, a Cayman Islands limited partnership (“Master II”), Sarissa Capital Athena Offshore Fund Ltd, a Cayman Islands private limited company (“Athena” and, together with Catapult, Hawkeye, ISP, Offshore and Master II, the “Direct Sarissa Beneficial Owners”), record holders of ordinary shares, par value 50 pence per share of the Company (the “Shares”), delivered a requisition notice (as amended, the “Requisition Notice”) in accordance with the United Kingdom Companies Act 2006 (the “Companies Act”), proposing (among other things) to adopt ordinary resolutions that would provide that, in the event any director is appointed after Amarin’s receipt of the Requisition Notice, each such director be removed from office as a director.

The following is the text of the proposed resolution:

“THAT in the event any director is appointed after the Company’s receipt of the general meeting requisition notice dated January 10, 2023, and prior to the general meeting, each such director be removed from office as a director of the Company with immediate effect.”

The Participants are bringing Proposal 2 for consideration at the general meeting because, prior to the General Meeting, Amarin may appoint directors to the Board without Shareholder approval and such appointments would mean the Board does not have enough open seats to seat the Nominees. Proposal 2 allows the Shareholders at the General Meeting to remove from the Board any such directors.

At the General Meeting, the Participants will seek to elect to the Board the following persons (each a “Nominee” and together the “Nominees”) by ordinary resolution, and at the General Meeting, the resolution for the election of each Nominee will be presented separately and on an individual basis as further described in this Proxy Statement and related Proxy Card:

The Beneficial Owners (as hereinafter defined) believe that meaningful shareholder representation on the Board would be extremely beneficial to Amarin and, therefore, its Shareholders. Moreover the Beneficial Owners believe that the Nominees’ knowledge of medicine, investments, operations, research and development, capital allocation,

partnerships and strategic transactions, corporate governance, and corporate finance, would be extremely beneficial to Amarin and, therefore, its Shareholders and will significantly improve the expertise and leadership of the Board. Each of the Nominees has consented to being named in this Proxy Statement and, if elected, to serve as a director, and the Beneficial Owners believe that each of the Nominees has the requisite set of skills to serve as a director of the Company.

If elected, the Nominees plan to engage collaboratively with the other members of the Board to enhance shareholder value, including by focusing on corporate governance, capital allocation, the Company’s approach to drug pricing and reimbursement and its European expansion. While the Nominees, if elected, would represent a minority of the Board, the Participants believe that the Nominees will bring strong experience, perspectives and expertise to the Board that will facilitate open dialogue among all directors.

Each Nominee and each of the other Participants has no interest in Amarin, other than through the beneficial ownership (if any) of Shares or other securities of the Company described in this Proxy Statement, including Annex A, and as follows:

Pursuant to the organizational documents of certain of the Beneficial Owners, Dr. Denner, Ms. Bonfiglio, Mr. DiPaolo, and Dr. Kostas may be the beneficiaries of indemnification obligations from certain of the Beneficial Owners for certain acts or omissions taken or suffered by such person (including any act or omission taken or suffered by them in reliance upon and in accordance with the opinion or advice of experts) that relates to, or in connection with the business of, the Beneficial Owners, including in respect of the matters referred to in this Proxy Statement.

Each Nominee and each other Participant may have an interest in the proposals being submitted for Shareholder vote at the General Meeting, including the election of directors, directly and indirectly: (i) through the beneficial ownership (if any) of the Shares or other securities of the Company described in this Proxy Statement, including Annex A; (ii) with respect to the Sarissa Beneficial Owners, through performance-related fees (if any) based in part on the value (and any appreciation thereof) of the assets held by the Sarissa Beneficial Owners; and (iii) with respect to Dr. Denner, Ms. Bonfiglio, Mr. DiPaolo, and Dr. Kostas, through their interests in the profits, if any, derived as a result of their roles at the Sarissa Beneficial Owners.

For additional information on the Participants, please see “Participants in Solicitation of Proxies” below and Annex A.

This Proxy Statement contains forward-looking statements. All statements contained herein that are not clearly historical in nature or that necessarily depend on future events are forward-looking, and the words “anticipate,” “believe,” “expect,” “potential,” “could,” “opportunity,” “estimate,” “plan,” and similar expressions are generally

intended to identify forward-looking statements. The statements contained herein that are not historical facts are based on current expectations, speak only as of the date of this Proxy Statement and involve risks, uncertainties and other factors that may cause actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by such statements. Assumptions relating to the foregoing involve judgments with respect to, among other things, future economic, competitive and market conditions and future business decisions, all of which are difficult or impossible to predict accurately and many of which are beyond the control of Sarissa Capital. Although Sarissa Capital believes that the assumptions underlying the forward-looking statements are reasonable as of the date of this Proxy Statement, any of the assumptions could be inaccurate and therefore, there can be no assurance that the forward-looking statements included herein will prove to be accurate and therefore actual results could differ materially from those set forth in, contemplated by, or underlying those forward-looking statements. In light of the significant uncertainties inherent in the forward-looking statements included herein, the inclusion of such information should not be regarded as a representation as to future results or that the objectives and strategic initiatives expressed or implied by such forward-looking statements will be achieved. Except to the extent required by applicable law, Sarissa Capital will not undertake and specifically declines any obligation to disclose the results of any revisions that may be made to any forward-looking statements herein to reflect events or circumstances after the date of such statements or to reflect the occurrence of anticipated or unanticipated events.

Sarissa Capital began investing in Amarin in 2021 because it believed that the Company’s shares were undervalued in light of the significant potential of its cardiovascular product, Vascepa/Vazkepa.

Sarissa Capital initiated active engagement with Amarin in March 2022 in light of, among other things, the significant decline in the Company’s market capitalization which Sarissa Capital believes was the result of, among other things, the Company’s poor approach to corporate governance (including lack of shareholder representation on the Board) and capital allocation, as well as its lack of strategy and failure and delay in executing on a variety of operational matters, including drug pricing and reimbursement and its European expansion.

During the second quarter of 2022, the Company and Sarissa Capital continued discussions. These discussions focused on the Company’s purported ongoing Board refreshment process, including the desire for Sarissa Capital to have representation on the Board given its status as the Company’s largest shareholder. During these interactions, Sarissa Capital highlighted, among other things, its prior experience at The Medicines Company, a similarly situated company in the cardiovascular space, noting the significant shareholder value that was generated following the appointment of a Sarissa Capital representative to the Board.

In light of the ongoing discussions with the Company at the time, Sarissa Capital determined not to submit a nomination notice seeking election of directors at the 2022 annual meeting. Instead, on June 15, 2022, Sarissa Capital announced that it would abstain from voting at the 2022 annual meeting. The Company held its 2022 annual meeting on July 27, 2022. At the 2022 annual meeting, nearly 50% of all votes cast were either votes against the Board or abstentions.

During August and September 2022, Sarissa Capital continued its dialogue with the Company. By the end of September 2022, approximately six months following the initiation of active engagement, Sarissa Capital determined that the Company was not taking Board refreshment seriously and had no intention of adding shareholder representation to the Board. As a result, on October 11, 2022, Sarissa Capital issued a press release indicating that it commenced the process to call a general meeting of shareholders of the Company.

Sarissa Capital determined to call a general meeting of shareholders for a variety of reasons. Over the past five years, Amarin has lost a substantial proportion of its market capitalization, with over $840 million in market capitalization being lost in 2022. Sarissa Capital believes that the significant destruction of shareholder value is attributable to, among other things, poor capital allocation decisions, the delayed response by the Board and management to significantly changing market dynamics in 2022, including cost cutting initiatives that were undertaken well after multiple generics entered the U.S. market, and poor execution of the Company’s European expansion, including a denial of reimbursement in Germany (the largest European market) and significant delays in other large markets such as France.

On January 10, 2023, Sarissa Capital delivered a Requisition Notice to the Company, requesting that the Company convene a general meeting to, among other things, the removal of Per Wold-Olsen as a director of the Company and the election of seven candidates to the Board, including three representatives of Sarissa Capital.

Following the submission of the Requisition Notice, counsel to Amarin delivered a letter to Sarissa Capital late afternoon on January 16, 2023. In the letter, among other things, Amarin (i) took the position that the director nomination proposals put forth by Sarissa Capital could only be considered by shareholders if 100% of the shares voting at the meeting allowed the proposals to proceed, and (ii) requested Sarissa Capital’s position regarding the outcome of the general meeting if the proposal to remove the chairman of the Board failed and each Nominee was elected to the Board, as this would result in the number of total directors exceeding the number of directors permitted by the Company’s organizational documents.

Without engaging at all with Sarissa Capital or its counsel, before market open on January 17, 2023, the Company filed its preliminary proxy statement which contemplated the introduction of an authorizing resolution that would require the approval of 100% of the shares voting at the meeting for the Sarissa Capital director nomination proposals to be voted on by shareholders. The preliminary proxy statement filed by the Company did not address in any way the outcome of the vote should the proposal to remove the chairman of the Board fail and each Nominee be elected to the Board.

On January 18, 2023, Sarissa Capital filed its preliminary proxy statement with the SEC, which contemplated separate resolutions for each Nominee and did not require the prior vote of 100% of the shares voting at the meeting for these proposals to be considered at the general meeting. Promptly following the filing of the preliminary proxy statement, counsel for Sarissa Capital engaged in dialogue with counsel to Amarin and explained Sarissa Capital’s view that Amarin’s interpretation of the Requisition Notice and local law was clearly not the intention of the organizational documents of the Company and would disenfranchise shareholders. During these conversations, counsel to Sarissa Capital recommended prompt resolution to the “authorizing resolution” issue to permit the general meeting to be convened and to not unnecessarily waste shareholder resources.

Following the outreach from counsel to Sarissa Capital and notwithstanding the request for prompt and collaborative resolution to these matters, on January 23, 2023, counsel to Amarin delivered a letter to counsel to Sarissa Capital again suggesting, among other things, that the Nominee proposals could only be put forth if an authorizing resolution is adopted by 100% of the shares voted at the meeting. To avoid further delay and waste of shareholder resources, on January 24, 2023, Sarissa Capital submitted a modified Requisition Notice to Amarin. Following the submission of this notice, the Company filed an amended preliminary proxy statement eliminating its prior position that the Sarissa Capital director nomination proposals could only be heard if 100% of the shares voting at the meeting permitted the proposals to proceed. In addition, to facilitate the prompt convening of the meeting without further delay, while reserving its rights, Sarissa Capital agreed that if the proposal to remove the chairman of the Board fails and each of the first six Nominees is elected to the Board, then the proposal with respect to the election of the final Nominee would not be considered at the general meeting.

On January 27, 2023, Sarissa Capital filed an amended preliminary proxy statement with the SEC.

On January 30, 2023, counsel to Sarissa Capital received a communication from counsel to Amarin on behalf of the chairman of the Board of the Company with a request that it be sent to a senior partner at Sarissa Capital. The communication noted the strong backgrounds of certain of the Nominees and the Company’s interest in potentially interviewing them as part of its purported Board refreshment process. However, none of the Nominees identified in the communication are Sarissa Capital representatives, further cementing Sarissa Capital’s concern that the Board is not interested in accountability associated with shareholder participation on the Board. On the same day, counsel to Sarissa Capital responded that Sarissa Capital appreciated the recognition of the strength of its Board slate (including Sarissa Capital’s ability to identify strong, value-add Board candidates) but that a direct dialogue between Sarissa Capital and the Company would be more efficient and that Sarissa Capital would welcome that engagement so long as it included the opportunity for shareholder representation on the Board.

On January 30, 2023, Sarissa Capital filed an amended preliminary proxy statement with the SEC.

According to the Articles and applicable law, each director nominated for election is elected, and each other proposal is approved, if (i) on a show of hands, a majority of shareholders present in person or by proxy and voting on the proposal vote in favor of such director or proposal, or (ii) on a poll, a majority of the shares present at the meeting in person or by proxy and voting on the proposal are voted in favor of such director. Abstentions and broker non-votes will have no effect on the vote outcome. As a result, your vote is extremely important. We urge you to vote FOR the removal of Mr. Wold-Olsen from the Board, FOR the removal of new directors, if any, that Amarin appoints to the Board after the receipt of the general meeting requisition notice dated January 10, 2023, and FOR the election of each Nominee pursuant to each separate resolution pertaining such Nominee.

If you attend the General Meeting and you beneficially own Shares but are not the record owner, including if your Shares are represented by ADSs, your mere attendance at the General Meeting WILL NOT be sufficient to vote your Shares or to cancel your prior given proxy card. Contact D.F. King & Co., Inc. at the number shown in this Proxy Statement for assistance or if you have any questions.

If you have any questions or require any assistance in executing your proxy, please call:

Only holders of record of Shares as of the close of business on January 23, 2023 (the “Record Date”) are entitled to notice of, and to attend and to vote at, the General Meeting and any adjournments or postponements thereof. According to the proxy statement filed by Amarin with the SEC on [•], 2023 (the “Amarin Proxy Statement”), as of the Record Date, there were outstanding [•] Shares. Shareholders of record at the close of business on the Record Date will be entitled to one vote on each matter to be voted upon at the General Meeting for each Share held on the Record Date.

As of the Record Date, the Sarissa Beneficial Owners (as defined below) may be deemed to beneficially own, within the meaning of Rule 13d-3 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), 25,210,000 Shares, representing approximately [•]% of outstanding Shares, as more fully described in Exhibit A. In addition, as of the Record Date, Mr. Sterling may be deemed to separately beneficially own, within the meaning of Rule 13d-3 under the Exchange Act, 69,772 Shares, representing approximately [•]% of outstanding Shares. The Sarissa Reporting Persons and Mr. Sterling may be deemed to have formed a group within the meaning of Rule 13d-5(b) under the Securities Exchange Act of 1934, as amended, and may be deemed to beneficially own, in the aggregate, 25,279,772 Shares representing approximately [•]% of the outstanding Shares. Percentages of outstanding Shares are based upon the [•] Shares stated to be outstanding as of the Record Date by the Company as set forth in the Amarin Proxy Statement. Mr. Sterling disclaims beneficial ownership of the Shares owned by the Sarissa Beneficial Owners. The Sarissa Beneficial Owners disclaim beneficial ownership of the Shares owned by Mr. Sterling. The Participants intend to vote such Shares FOR the removal of Mr. Wold-Olsen from the Board, FOR the removal of new directors, if any, that Amarin appoints to the Board after the receipt of the general meeting requisition notice dated January 10, 2023, and FOR the election of each Nominee pursuant to each separate resolution pertaining such Nominee.

In addition to the Nominees (who are Ms. Bonfiglio, Dr. Cohen, Mr. DiPaolo, Mr. Horn, Dr. Kostas, Mr. Sterling, and Ms. Sullivan and whose backgrounds are described in further detail below), the participants (the “Participants”) in the solicitation of proxies from Shareholders are listed on the cover page to this Proxy Statement.

Sarissa Capital Fund GP LLC, a Delaware limited liability company (“Fund GP LLC”) is the general partner of Sarissa Capital Fund GP LP, a Delaware limited partnership (“Fund GP LP”). Fund GP LP is (i) a special member of Catapult, (ii) the general partner of Hawkeye and ISP, and (iii) the sole member of Sarissa Capital Offshore Fund GP LLC, a Delaware limited liability company (“Offshore GP”). Offshore GP is the general partner of Offshore, Master II and Athena. Sarissa Capital Management GP LLC, a Delaware limited liability company (“Management GP”) is the general partner of Sarissa Capital. Sarissa Capital is (i) a registered investment advisor to Hawkeye, ISP, Offshore, Master II, Athena, and Atom Master Fund LP (“Atom”), and (ii) the managing member of Catapult. Dr. Denner is the managing member of Fund GP LLC and Management GP (Dr. Denner, collectively with Fund GP LLC, Fund GP LP, Offshore GP, Management GP, Sarissa Capital, Atom, and the Direct Sarissa Beneficial Owners, the “Sarissa Beneficial Owners”). Dr. Denner is also (i) the Chief Investment Officer of Sarissa Capital, and (ii) a member of the board of directors of Athena. As such, Dr. Denner is in a position, indirectly, to determine the investment and voting decisions made by each of the other Sarissa Beneficial Owners.

Annex A sets forth, as to each Participant (including the Nominees), all transactions in securities of Amarin effected during the past two years and their beneficial ownership of securities of Amarin.

Except as set forth herein, (a) each Participant in the solicitation is not, and was not within the past year, a party to any contract, arrangement or understanding with any person with respect to any securities of Amarin, including, but not limited to, joint ventures, loan or option arrangements, puts or calls, guarantees against loss or guarantees of profit, division of losses or profits, or the giving or withholding of proxies; (b) no Participant in this solicitation and no associate of any Participant in this solicitation has any arrangement or understanding with any person with respect to (x) any future employment by Amarin or its affiliates or (y) any future transactions to which Amarin or any of its affiliates will or may be a party; (c) no Participant in this solicitation and no associate of any Participant in this solicitation owns beneficially, directly or indirectly, any securities of Amarin or any subsidiary of Amarin; and (d) no Participant in this solicitation and no associate of any Participant in this solicitation was a party to a transaction that is required to be described under Item 404(a) of Regulation S-K.

Except as set forth herein, (a) no Nominee, nor any associate of any Nominee, is a party adverse to Amarin or any of its subsidiaries or has a material interest adverse to Amarin or any of its subsidiaries in any material proceeding; (b) there is no event that occurred during the past 10 years with respect to a Nominee that is required to be described under Item 401(f) of Regulation S-K; and (c) there is no arrangement or understanding between a Nominee and any other person pursuant to which he or she is to be selected as a nominee.

The Board currently consists of nine directors. Pursuant to the Articles, the Board shall be comprised of not more than fifteen directors, and the Board may appoint additional directors so long as the total number of directors does not exceed the maximum number fixed in accordance with the Articles. Pursuant to the Articles, directors may be removed and replaced by ordinary resolution of the Shareholders.

At the General Meeting, the Participants will seek to remove Mr. Wold-Olsen from office as a director of the Company.

The following is the text of the proposed resolution:

“THAT Per Wold-Olsen be removed from office as a director of the Company with immediate effect.”

The Participants are bringing Proposal 1 for consideration at the general meeting because, under the watch of Mr. Wold-Olsen, as Chairman, the Company has lost significant shareholder value, failed to deliver on business objectives communicated to shareholders, and failed to advance shareholder representation on the Board and so as to have enough open seats of the Board to seat the Nominees.

The following is the text of the proposed resolution:

“THAT in the event any director is appointed after the Company’s receipt of the general meeting requisition notice dated January 10, 2023, and prior to the general meeting, each such director be removed from office as a director of the Company with immediate effect.”

The Participants are bringing Proposal 2 for consideration at the general meeting because, prior to the General Meeting, Amarin may appoint directors to the Board without Shareholder approval and such appointments would mean the Board does not have enough open seats to seat the Nominees. Proposal 2 allows the Shareholders at the General Meeting to remove from the Board any such directors.

Section 303 of the Companies Act provides that the directors of a company are required to call a general meeting once the company has received requests to do so from members representing at least 5% of such of the paid-up capital of the company as carries the right of voting at general meetings of the company, which such requests state the general nature of the business to be dealt with at the meeting and may include the text of a resolution that may be properly moved and is intended to be moved at the meeting. The Direct Sarissa Beneficial Owners have delivered the Requisition Notice in accordance with the Companies Act, proposing (among other things) to adopt an ordinary resolution to appoint each of Ms. Bonfiglio, Dr. Cohen, Mr. DiPaolo, Mr. Horn, Dr. Kostas, Mr. Sterling, and Ms. Sullivan as a director of the Company pursuant to each separate resolution pertaining such Nominee.

The Articles provide that, at every annual general meeting, at least one-third of the directors at the time shall retire from office (or, if the number of directors at the time is not a multiple of three, then the number nearest to but not exceeding one-third shall retire from office). The Articles further provide that the directors to retire on each occasion include, so far as necessary to obtain the number required, any director who wishes to retire and not offer himself for re-election and any further directors to retire shall be those who have been longest in office since their last election. If elected, the Nominees will hold office until their successors are elected and qualified, unless they resign or their seats become vacant due to removal or other cause in accordance with the Articles. As a result, if the director in question is re-elected at each annual general meeting at which he or she is required to retire, then his or her appointment could be for an unlimited period. Background information about the Nominees is set forth below and Annex A.

If elected, the Nominees would be a minority of the directors and will not alone be able to adopt resolutions. However, the Nominees expect to be able to actively engage other Board members in full discussion of the issues facing the Company and resolve them together. By utilizing their experience and working constructively with Board members, the Nominees believe they can effect positive change at the Company.

As described above, pursuant to the organizational documents of certain of the Beneficial Owners, Ms. Bonfiglio, Mr. DiPaolo, Dr. Kostas, and certain other Participants may be the beneficiaries of certain indemnification obligations of such Beneficial Owners for certain actions taken on behalf of, or in connection with the business of, such Beneficial Owners, including in respect of the matters referred to in this Proxy Statement.

The Nominees are independent under the independence standards applicable to the Company under paragraph (a)(1) of Item 407 of Regulation S-K and, if elected, each would be an “independent director” in accordance with the listing standards of the Nasdaq Stock Market LLC.

Since March 2014 and February 2017, Patrice Bonfiglio has served as the Chief Financial Officer and Chief Compliance Officer of Sarissa. From 2013 to 2014, Ms. Bonfiglio was also Manager of Accounting and Operations of Sarissa. From 2012 to 2013, Ms. Bonfiglio served as the Head of Operations for commodities hedge fund Arbalet Capital Management, LP, where she was responsible for managing the firm’s spinout from hedge fund Arrowhawk Capital Partners, LLC, covering operations, accounting, and compliance. Prior to the spinout of Arbalet, Ms. Bonfiglio was the Operations Manager at Arrowhawk Capital Partners, LLC from 2010 to 2012, managing all aspects of the firm’s day to day operations and contributing to the accounting and compliance teams of the multi-strategy hedge fund. From 2008 to 2010, Ms. Bonfiglio served as Senior Accountant at Ridgefield Capital Asset Management, where she was responsible for the operations and accounting of the portfolio funds and managed accounts. From 2006 to 2008, Ms. Bonfiglio was an Associate and Fund Accountant at Pequot Capital Management, Inc. Ms. Bonfiglio received her B.S. degree from Temple University.

Ms. Bonfiglio is well-qualified to serve as a member of the Board due to her significant operational, accounting, finance and compliance expertise.

Dr. Paul Cohen is the Albert Resnick, MD Associate Professor, Head of the Laboratory of Molecular Metabolism, and Senior Attending Physician at The Rockefeller University. At the Rockefeller University, Dr. Cohen has served as an Associate Professor since 2021 and as an Assistant Professor from 2015 to 2021. Dr. Cohn has also served as a scientific advisor to Hoxton Farms, a biotech startup based in London, since September 2021. Since 2016, Dr. Cohen has been a practicing cardiologist at Memorial Sloan Kettering Cancer Center. Since 2015, Dr. Cohen has been a Senior Attending Physician at the Rockefeller University Hospital. He is a graduate of the Tri-Institutional MD-PhD Program, where he completed his PhD research at Rockefeller studying the unique metabolic effects of the hormone leptin. He then completed an Internal Medicine Residency at Columbia and a Cardiology Fellowship at Brigham and Women’s Hospital. He performed postdoctoral research training at the Dana Farber Cancer Institute studying transcriptional determinants of adipocyte identity. Dr. Cohen received his MD from Weill Cornell Medical College, his PhD from The Rockefeller University and his AB from Harvard College.

Dr. Cohen is well-qualified to serve as a member of the Board due to his significant scientific, medical and research and development expertise.

Since February 2013, Mark DiPaolo has served as the Senior Partner and General Counsel of Sarissa. From 2005 to 2013, Mr. DiPaolo served as a senior member of Carl Icahn’s investment team at Icahn Capital, working on all aspects of Mr. Icahn’s investment strategy. During that time, Mr. DiPaolo worked closely with Dr. Alexander Denner, the Founder and Chief Investment Officer of Sarissa Capital, on many healthcare activist campaigns and achieved many favorable investment outcomes for investors. Mr. DiPaolo worked with Dr. Denner in founding Sarissa Capital and has been instrumental in the development and execution of Sarissa Capital’s investments and strategy. Prior to working at Icahn, Mr. DiPaolo was an M&A attorney at Willkie Farr & Gallagher LLP. Since February 2018, Mr. DiPaolo has served on the board of directors of Innoviva, Inc. From August 2017 to September 2018, Mr. DiPaolo also served on the board of directors of Novelion Therapeutics Inc. Mr. DiPaolo received his B.A. degree from Fordham University and his J.D. degree from Georgetown University.

Mr. DiPaolo is well-qualified to serve as a member of the Board due to his significant investments, operations, capital allocation, corporate governance, corporate finance, and mergers and acquisitions expertise.

Mr. Horn is the founder and managing member of Loring Capital Advisors, LLC, a firm providing investment advisory and consulting services to hedge fund managers, asset management firms, and early-stage and start-up businesses. Mr. Horn served as the Chief Executive Officer and a director of Forest Road Acquisition Corp. from

September 2020 to June 2021, when it consummated a business combination with The Beachbody Company. From 2003 to 2015, Mr. Horn served as Chief Operating Officer and a member of the Management Committee and Valuation Committee of Elliott Management Corporation, a global multi-strategy firm, where he was responsible for global management and oversight of operational, support and control functions of the firm’s investment advisory business. Prior to Elliott, Mr. Horn spent 16 years at Merrill Lynch, Pierce, Fenner & Smith Incorporated, serving in various capacities, including Global Head of Leveraged Finance, Head of Latin America Debt, and Chief of Staff to the Chairman and President. Mr. Horn began his career in private practice as a corporate and securities attorney. Since October 2021, Mr. Horn has served as an advisory board member of Sharp Alpha, a sports betting and gaming venture capital fund. Mr. Horn also served on the board of directors of Sarissa Capital Acquisition Corp., a special purpose acquisition company sponsored by Sarissa Capital from October 2021 to November 2022. Since March 2021 Mr. Horn has served as a director of Forest Road Acquisition Corp. II, a special purpose acquisition company. In addition, since January 2019, Mr. Horn has served as a director of Caliper Holdings, a company engaged in the consumer and commercial ingredients food and beverage business, and since March 2018, Mr. Horn has served as a director of ShopOne Centers REIT, Inc., an owner and operator of shopping malls. In addition, in July 2019, Mr. Horn was appointed to the strategic advisory board of Investcorp Strategic Capital Partners, a fund established to assemble a diverse portfolio of general partnership stakes in alternative asset managers. In December 2019, Mr. Horn joined the Strategic Advisory Board of the Forest Road Company, LLC, a specialty finance and tax services company that lends against U.S. tax credits and provides capital in the media space. From April 2016 to November 2019, Mr. Horn served on the board of directors of Empire Resorts, Inc., which operates in the gaming and hospitality industries, where he served as Chairperson of the audit committee and as Chairperson of the special committee in its review and approval of an acquisition transaction pursuant to which Empire became a privately-held entity. Mr. Horn also serves on the board of directors for the Binghamton University Foundation and is a member of the Foundation investment committee. He is also a member of the board of directors of PeacePlayers International, a non-profit organization that uses the game of basketball to educate and unite children in areas of conflict around the world. Mr. Horn received his J.D. (cum laude) from Georgetown University Law Center and his B.A. degrees in Economics and Political Science from Binghamton University, where he graduated Phi Beta Kappa with highest honors.

Mr. Horn is well-qualified to serve as a member of the Board due to his significant investments, operations, capital allocation, partnerships and strategic collaboration, corporate governance, corporate finance and mergers and acquisitions expertise.

Since 2016, Odysseas Kostas has served as a Partner and Senior Managing Director of Sarissa, and he currently also serves as Head of Research. He most recently served as a director at Evercore ISI (formerly ISI), where he was employed from 2011 to 2015, covering the biotechnology and pharmaceutical industries. Previously, he practiced internal medicine as part of the Yale New Haven Health system and was engaged as a consultant to various biotechnology companies. Since December 2017, Dr. Kostas has served as Chairman of the board of directors of Innoviva, Inc., and since February 2020, has served on the board of directors of Armata Pharmaceuticals, Inc. Dr. Kostas also served on the board of directors of Enzon Pharmaceuticals from 2013 to 2020. In addition, from 2010 to 2011, Dr. Kostas served on the board of directors of Mast Therapeutics (formerly known as ADVENTRX Pharmaceuticals). Dr. Kostas received his S.B. degree from the Massachusetts Institute of Technology and his M.D. degree from the University of Texas Southwestern Medical School.

Dr. Kostas is well-qualified to serve as a member of the Board due to his significant medicine, investments, operations, research and development, capital allocation, partnerships and strategic collaboration, corporate governance, corporate finance and mergers and acquisitions expertise.

Louis Sterling III is a private investor targeting small-cap public equities and select fast-growth private companies, particularly in the health, wellness, and cannabis industries. Prior to 2017, he was a managing director of BondFactor, a firm specializing in insuring municipal bonds. Since December 2021, Mr. Sterling has served as a director of the Green Organic Dutchman Holdings Ltd., a sustainable global cannabis company, and currently serves as Chair of the Corporate Governance & Nominating Committee and as a member of the Compensation Committee. Prior to 2017, Mr. Sterling worked in investment banking (corporate finance/M&A) at Goldman Sachs, middle-market private equity at Lincolnshire Management, and fin-tech at BondFactor. Mr. Sterling received his J.D. from Harvard Law School, his MBA from Harvard Business School and his B.B.A. from Howard University.

Mr. Sterling is well-qualified to serve as a member of the Board due to his significant investments, operations, capital allocation, corporate finance and mergers and acquisitions expertise.

Diane E. Sullivan founded her own consulting firm in 2020 which specializes in strategic development for life sciences companies. From 2018 to 2020, Ms. Sullivan served as Chief Commercial Officer of The Medicines Company (“MDCO”), until its $9.7B acquisition by Novartis. Prior to her time at MDCO, Ms. Sullivan was Vice President, Market Access & Patient Strategies at AstraZeneca from 2013 to 2017. She was Vice President, Specialty Payer & Channel Group at Pfizer from 2009 to 2013 and prior to the acquisition, was Vice President, Healthcare Systems Marketing at Wyeth in 2008. Before Wyeth, Ms. Sullivan spent 12 years, in a series of strategy, marketing, brand management, business development, and integration roles at GlaxoSmithKline. She began her career at IBM and was a member of the team that launched IBM’s entry into the Health Data Networking business. Ms. Sullivan served on the board of directors of OrthogenRx, a privately held medical device company acquired by Avanos Medical in 2022, from 2018 to 2022. She currently sits on the Life Science Council of Springboard Enterprises and has served on the boards of industry and nonprofit groups including the National Association of Specialty Pharmacy, the Advisory Board of the Professional Women’s Roundtable, Leadership Philadelphia, and Support Center for Child Advocates. Ms. Sullivan received a B.A. from Dickinson College. She also graduated from IBM’s intensive two-year marketing and account management training program as well as IBM’s customized version of an MBA program.

Ms. Sullivan is well-qualified to serve as a member of the Board due to her significant investments, operations, research and development, capital allocation, partnerships and strategic collaboration, corporate governance, corporate finance and mergers and acquisitions expertise.

The Participants know of no other business to be presented at the General Meeting. If any other matters should properly come before the General Meeting, it is intended that the persons named on the enclosed BLUE Proxy Card will vote that proxy on such other matters in accordance with their judgment.

Amarin is registered in England & Wales and is therefore subject to the Companies Act, which, together with the Articles, governs the processes for shareholder voting at general meetings. There are a number of differences between English and U.S. law in relation to voting. At the General Meeting, a resolution put to the vote of the meeting shall be decided on a show of hands unless a poll is demanded (either before or immediately after the result of a show of hands on that resolution is declared or on the withdrawal of any other demand for a poll) by (a) the Chairman of the meeting, (b) at least two shareholders of the Company entitled to vote at the meeting, (c) a shareholder or shareholders of the Company representing not less than one-tenth of the total voting rights of all shareholders having the right to vote at the meeting (excluding any voting rights attached to shares in the Company that are held as treasury shares) or (d) a shareholder or shareholders of the Company holding shares conferring a right to vote at the meeting being shares on which an aggregate sum has been paid up equal to not less than one-tenth of the total sum paid up on all shares conferring that right (excluding any shares in the Company conferring a right to vote at the meeting that are held as treasury shares). The Participants intend to demand a poll at the General Meeting so as to ensure each Shareholder gets one vote per Share held.

Only holders of record of the Shares at the close of business on the Record Date, are entitled to notice of, and to attend and to vote at, the General Meeting. On the Record Date, approximately [•] Shares were issued and [•] were outstanding and entitled to vote at the General Meeting, of which approximately [•] were held in the name of Citibank, N.A., as Depositary, (the “Depositary”) which issues Company-sponsored American Depositary Shares (“ADSs”) which, in turn, each represent one Share. With respect to all matters to be voted on at the General Meeting, each Shareholder present has only one vote unless demand is made for a vote on a poll (in which case each Shareholder gets one vote per Share held). The presence, in person or by proxy, of at least two Shareholders who hold Shares as of the Record Date will constitute a quorum under English law for the transaction of business at the General Meeting. At any adjournment of the General Meeting, if a quorum is not present within 15 minutes from the time appointed for such meeting, one person entitled to be counted in a quorum present at the adjournment shall be a quorum.The Amarin Proxy Statement states that (i) consistent with the marketplace rules of Nasdaq, the Company will seek to ensure that the Shareholders present at the General Meeting in person or by proxy represent at least one third of the Company’s outstanding shares of voting stock, and (ii) if a quorum is present at the General Meeting under English law, but is insufficient to meet the Nasdaq one-third threshold, the Chairman of the General Meeting will propose an ordinary resolution of the Company to seek consent (which is passed by a simple majority of members present (in person or by proxy) at the General Meeting voting in favor of it) to adjourn the General Meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies to establish a quorum meeting the Nasdaq threshold.

Persons who own Shares indirectly on the Record Date through a brokerage firm, bank or other financial institution, including persons who own Shares in the form of ADSs through the Depositary, must return a voting instruction form to have their shares or the shares underlying their ADSs, as the case may be, voted on their behalf. Under U.S. national securities exchange rules, if such person does not provide voting instructions, their brokerage firm, bank or other financial institution is only allowed to vote their shares on routine matters and cannot vote their shares on any non-routine matter. A “broker non-vote” occurs when a brokerage firm, bank, or other financial institution holding the shares for a beneficial owner votes on one proposal but does not vote on another proposal because, with respect to such other proposal, the brokerage firm, bank or financial institution does not have discretionary voting power and has not received instructions from the beneficial owner as to how to vote such shares. We are not aware of any routine matters being presented at the General Meeting. For non-routine matters, brokers, or other nominees, do not have authority, discretionary or otherwise, to vote the shares of a beneficial owner unless they receive proper instructions to do so from the beneficial owner in a timely manner. We encourage you to provide voting instructions to your brokerage firm, bank or other financial institution by giving your proxy to them as promptly as possible to ensure that your shares will be voted at the General Meeting according to your instructions. You should receive directions from your brokerage firm, bank or other financial institution about how to submit your proxy to them at the time you receive this Proxy Statement.

At the General Meeting, broker non-votes and abstentions will be counted for the purpose of determining the presence or absence of a quorum, but will not be counted for the purpose of determining the number of votes cast on a given proposal. The required vote for each of the proposals expected to be acted upon at the General Meeting is described below.

With respect to PROPOSAL 1 – REMOVAL OF CHAIRMAN PER WOLD-OLSEN FROM THE BOARD – This proposal will be approved if (i) on a show of hands, a majority of Shareholders present in person or by proxy and voting on the proposal vote in favor of the resolution or (ii) on a poll, a majority of the Shares present at the meeting in person or by proxy and voting on the proposal are voted in favor of the resolution. As a result, abstentions and broker non-votes will have no effect on the vote outcome. The Amarin Proxy Statement states that the Company will conduct the vote by way of a poll.

With respect to PROPOSAL 2 – REMOVAL OF NEW DIRECTORS – This proposal will be approved if (i) on a show of hands, a majority of Shareholders present in person or by proxy and voting on the proposal vote in favor of the resolution or (ii) on a poll, a majority of the Shares present at the meeting in person or by proxy and voting on the proposal are voted in favor of the resolution. As a result, abstentions and broker non-votes will have no effect on the vote outcome. The Amarin Proxy Statement states that the Company will conduct the vote by way of a poll.

With respect to PROPOSALS 3 THROUGH 8 – ELECTION OF DIRECTORS – Each director nominated for election is elected if (i) on a show of hands, a majority of Shareholders present in person or by proxy and voting on the proposal vote in favor of such director or (ii) on a poll, a majority of the Shares present at the meeting in person or by proxy and voting on the proposal are voted in favor of such director. As a result, abstentions and broker non-votes will have no effect on the vote outcome. The Amarin Proxy Statement states that the Company will conduct the vote by way of a poll.

With respect to PROPOSAL 9 – ELECTION OF DIRECTORS – If Proposal 1 is not approved and each of Proposals 3, 4, 5, 6, 7 and 8 are approved, then the Board does not have enough open seats to seat all of the Nominees. In that context, Amarin has advised the Participants that Proposal 9 would not be put before the General Meeting. If Proposal 9 is put before the General Meeting, the director nominated for election pursuant to Proposal 9 is elected if (i) on a show of hands, a majority of Shareholders present in person or by proxy and voting on the proposal vote in favor of such director or (ii) on a poll, a majority of the Shares present at the meeting in person or by proxy and voting on the proposal are voted in favor of such director. As a result, abstentions and broker non-votes will have no effect on the vote outcome. The Amarin Proxy Statement states that the Company will conduct the vote by way of a poll.

As explained in the detailed instructions on your BLUE Proxy Card, there are three ways Persons who hold Shares registered in their own name the Record Date may vote. Such Persons may:

Whether or not you are able to attend the General Meeting, you are urged to complete the enclosed BLUE Proxy Card and lodge it at the office of the Registrars so as to be received by no later than the Ordinary Share Instruction Date. All valid proxies received prior to the meeting will be voted. If you specify a choice with respect to any item by marking the appropriate box on the proxy, the Shares will be voted in accordance with that specification. IF NO SPECIFICATION IS MADE, THE SHARES WILL BE VOTED (I) FOR THE REMOVAL OF MR. WOLD-OLSEN FROM THE BOARD, (II) FOR THE REMOVAL OF NEW DIRECTORS, IF ANY, THAT AMARIN APPOINTS TO THE BOARD AFTER THE RECEIPT OF THE GENERAL MEETING REQUISITION NOTICE DATED JANUARY 10, 2023, (III) FOR EACH OF MS. BONFIGLIO, DR. COHEN, MR. DIPAOLO, MR. HORN, DR. KOSTAS, MR. STERLING, AND MS. SULLIVAN TO SERVE AS A DIRECTOR PURSUANT TO EACH SEPARATE RESOLUTION PERTAINING SUCH NOMINEE, AND (IV) IN THE PROXY HOLDERS’ DISCRETION AS TO OTHER MATTERS THAT MAY PROPERLY COME BEFORE THE GENERAL MEETING.

If you have any questions or require any assistance in executing your proxy, please call:

Persons who hold ADSs through a bank, broker or other nominee on the Record Date should receive documentation and instructions for voting such ADSs at the General Meeting, including the ADS voting instruction form, through such intermediary. The intermediary holding your account is considered the holder of record. Please reach out to that intermediary to provide your voting instructions.

ADS holders are not entitled to vote directly at the General Meeting, but an Amended and Restated Deposit Agreement dated as of November 4, 2011 (the “Deposit Agreement”), exists among the Company, the Depositary and all holders and beneficial owners of ADSs issued thereunder pursuant to which registered holders of ADSs as of the Record Date are entitled to instruct the Depositary as to the exercise of voting rights pertaining to the Shares so represented. The Depositary has agreed that it will endeavor, insofar as practicable, to vote (in person (if permitted) or by delivery to the Company of a proxy) the Shares registered in the name of the Depositary, in accordance with the instructions of the ADS holders. In the event that the Depositary timely receives voting instructions from an ADS holder which fail to specify the manner in which the Depositary is to vote the Shares represented by such holder’s ADSs, the Depositary will deem such ADS holder (unless otherwise specified in the notice distributed to ADS holders) to have instructed the Depositary to vote in favor of the items set forth in such voting instructions. Instructions from ADS holders must be sent to the Depositary so that the instructions are received by no later than 10:00 a.m. New York time on February 22, 2023 (the “ADS Instruction Date”). ADS holders are therefore strongly encouraged to submit their voting instruction form as soon as possible. Shares represented by the ADSs for which ADS holders have not timely submitted valid voting instructions shall not be voted.

Persons who own Shares indirectly on the Record Date through a bank, broker or other nominee, must return a voting instruction form to such bank, broker or other nominee to have their Shares voted on their behalf. We encourage you to provide voting instructions to your bank, broker or other nominee by giving your proxy to them as promptly as possible to ensure that your Shares will be voted at the General Meeting according to your instructions. You should receive a BLUE voting instruction form from your bank, broker or other nominee about how to submit your voting instructions to them at the time you receive this Proxy Statement.

Persons who own Shares indirectly on the Record Date who wish to attend the General Meeting and vote in person should contact their bank, brokerage firm or other nominee holding Shares on their behalf in order to obtain a “legal proxy” which will allow them to both attend the meeting and vote in person. Without a legal proxy, such persons cannot vote in person at the General Meeting because their bank, broker or other nominee may have already voted or returned a broker non-vote on their behalf.

Only holders of record as of the close of trading on the Nasdaq on the Record Date will be entitled to vote. If you were a holder of Shares or an ADS holder of record on the Record Date, you will retain your voting rights at the General Meeting even if you sell such Shares or ADSs after the Record Date. Accordingly, it is important that you vote the Shares or ADSs held by you on the Record Date, or grant a proxy to vote such Shares or ADSs, even if you sell such Shares or ADSs after the Record Date.

Persons who hold Shares directly may revoke or change their proxy instructions at any time prior to the vote at the General Meeting by:

Although a revocation is effective if delivered to Amarin, the Beneficial Owners request that either the original or a copy of any revocation be mailed to the Beneficial Owners c/o D.F. King & Co., Inc., 48 Wall Street, New York, NY 10005, so that the Beneficial Owners will be aware of all revocations.

Persons who hold Shares represented by ADSs or held by a bank, broker or other nominee and who wish to change or revoke their voting instructions should contact such intermediary for information on how to do so. Indirect shareholders are therefore strongly encouraged to submit their voting instructions as soon as possible. Instructions from ADS holders must be sent to the Depositary so that the instructions are received by no later than the ADS Instruction Date.

Some banks, brokers and other nominee record holders may be participating in the practice of “householding” proxy statements and annual reports. This means that only one copy of this Proxy Statement may have been sent to multiple stockholders in your household. We will promptly deliver a separate copy of the document to you if you write to our proxy solicitor, D.F. King & Co., Inc., at the address set forth on the back cover of this Proxy Statement or call toll free at (800) 331-7024. If you want to receive separate copies of our proxy materials in the future, or if you are receiving multiple copies and would like to receive only one copy for your household, you should contact your bank, broker or other nominee record holder, or you may contact our proxy solicitor at the above address and phone number.

Solicitation of proxies will be made by the Participants. In connection therewith, the Participants have retained D.F. King & Co., Inc. (“D.F. King”) to conduct the solicitation, for which D.F. King is to receive a fee of up to $[•]. Sarissa Capital has agreed to indemnify D.F. King against certain liabilities and expenses. Proxies may be solicited

by mail, courier services, Internet, advertising, telephone or telecopier or in person. It is anticipated that D.F. King will employ up to 25 persons to solicit proxies from Shareholders for the General Meeting. The total expenditures in furtherance of, or in connection with, the solicitation of proxies is approximately $250,000 to date, and is estimated to be approximately $1,250,000 in total.

In addition, it is anticipated that certain regular employees of the Sarissa Beneficial Owners may participate in the solicitation of proxies in support of the proposals set forth herein. Such employees will receive no additional consideration if they assist in the solicitation of proxies.

The Sarissa Beneficial Owners will pay all costs associated with this solicitation. Such Sarissa Beneficial Owners may decide to seek reimbursement from the Company for such expenses if any Nominee is elected, but such reimbursement shall not be submitted to the shareholders of the Company for a vote thereon.

Certain information relating to Amarin is omitted from this Proxy Statement. Such information includes interests of certain persons in matters to be acted upon at the General Meeting, the securities of Amarin held by Amarin’s directors, executive officers and 5% shareholders, information regarding the directors and management of Amarin, and the date by which proposals of security holders intended to be presented at the next annual general meeting of Shareholders must be received by Amarin. Please refer to the Amarin Proxy Statement for such information. The Participants take no responsibility for the accuracy or completeness of any information contained in or taken from Amarin’s public filings.

Fund GP LLC is the general partner of Fund GP LP. Fund GP LP is (i) a special member of Catapult, (ii) the general partner of Hawkeye and ISP, and (iii) the sole member of Offshore GP. Offshore GP is the general partner of Offshore, Master II and Athena. Management GP is the general partner of Sarissa Capital. Sarissa Capital is (i) a registered investment advisor to Hawkeye, ISP, Offshore, Master II, Athena, and Atom, and (ii) the managing member of Catapult. Dr. Denner is the managing member of Fund GP LLC and Management GP. Dr. Denner is also (i) the Chief Investment Officer of Sarissa Capital, and (ii) a member of the board of directors of Athena. As such, Dr. Denner is in a position, indirectly, to determine the investment and voting decisions made by each of the other Beneficial Owners.

The principal business address of each of the Participants, other than Dr. Cohen, Mr. Horn, Mr. Sterling, and Ms. Sullivan, is c/o Sarissa Capital Management LP, 660 Steamboat Road, 3^rd Floor, Greenwich, CT 06830. The principal business address of Dr. Cohen is 504 East 63^rd Street, New York, NY 10065. The principal business address of Mr. Horn is 57 Maria Road, Woodcliff Lake, NJ 07677. The principal business address of Mr. Sterling is 133 N. Gale Drive, Beverly Hills, CA 90211. The principal business address of Ms. Sullivan is 183 S. Spring Mill Road, Villanova, PA 19085.

Fund GP LLC is primarily engaged in the business of serving as the general partner of Fund GP LP. Fund GP LP is primarily engaged in the business of serving as the general partner or member of certain investment funds (including Catapult, Hawkeye, and Offshore GP). Offshore GP is primarily engaged in the business of serving as the general partner or member of certain investment funds (including, Offshore, Master II, and Athena). Management GP is primarily engaged in the business of serving as the general partner of Sarissa Capital. Sarissa Capital is primarily engaged in the business of serving as a registered investment adviser to certain investment funds (including Catapult, Hawkeye, ISP, Offshore, Master II, Athena, and Atom). Dr. Denner is primarily engaged in the business of serving as the Chief Investment Officer of Sarissa Capital. Each of Catapult, Hawkeye, ISP, Offshore, Master II, Athena, and Atom is primarily engaged in the business of investing in securities.

As of the Record Date, the Sarissa Beneficial Owners may be deemed to beneficially own, within the meaning of Rule 13d-3 under the Exchange Act, 25,210,000 Shares, representing approximately [•]% of outstanding Shares. In addition, as of the date hereof, Mr. Sterling may be deemed to separately beneficially own, within the meaning of Rule 13d-3 under the Exchange Act, 69,772 Shares, representing approximately [•]% of outstanding Shares. The Sarissa Reporting Persons and Mr. Sterling may be deemed to have formed a group within the meaning of Rule 13d-5(b) under the Securities Exchange Act of 1934, as amended, and may be deemed to beneficially own, in the aggregate, 25,279,772 Shares representing approximately [•]% of the outstanding Shares. Percentages of outstanding Shares are based upon the [•] Shares stated to be outstanding as of the Record Date by the Company as set forth in the Amarin Proxy Statement. Mr. Sterling disclaims beneficial ownership of the Shares owned by the Sarissa Beneficial Owners. The Sarissa Beneficial Owners disclaim beneficial ownership of the Shares owned by Mr. Sterling.

Catapult has shared voting and dispositive power, except as described herein, with regard to 4,298,200 Shares, of which 1,224,123 are owned of record as of the date hereof. Hawkeye has shared voting and dispositive power, except as described herein, with regard to 3,928,800 Shares, all of which are owned of record as of the date hereof. ISP has shared voting and dispositive power, except as described herein, with regard to 6,663,377 Shares, of which 5,453,377 are owned of record as of the date hereof. Offshore has shared voting and dispositive power, except as described herein, with regard to 6,188,100 Shares, of which 6,187,100 are owned of record as of the date hereof. Master II has shared voting and dispositive power, except as described herein, with regard to 342,600 Shares, all of which are owned of record as of the date hereof. Athena has shared voting and dispositive power, except as described herein, with regard to 3,164,000 Shares, all of which are owned of record as of the date hereof. Atom has shared voting and dispositive power, except as described herein, with regard to 624,923 Shares. Offshore GP has shared voting and dispositive power with regard to 9,694,700 of the Shares and may be deemed to indirectly beneficially own such Shares. Each of Fund GP LLC and Fund GP LP has shared voting and dispositive power with regard to 17,921,700 of the Shares and may be deemed to indirectly beneficially own such Shares. Each of Sarissa Capital, Management GP and Dr. Denner has shared voting and dispositive power with regard to the Shares described in this paragraph and may be deemed to indirectly beneficially own such Shares. None of the Shares beneficially owned by Mr. Sterling are included in the amounts set forth in this paragraph.

The following table indicates the date of each purchase and sale of securities of the Company by the Participants within the past two years and the number of securities in each such purchase and sale. No part of the purchase price or market value of the securities listed below is represented by funds borrowed or otherwise obtained for the purpose of acquiring or holding such securities.