Deposit Agreement

Exhibit 4.01

SHIRE plc

AND

JPMORGAN CHASE BANK, N.A.
As Depositary

AND

HOLDERS OF AMERICAN DEPOSITARY RECEIPTS

Deposit Agreement

Dated as of November 21, 2005

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      DEPOSIT AGREEMENT dated as of November 21, 2005 (the "Deposit Agreement") among SHIRE plc and its successors (the "Company"), JPMORGAN CHASE BANK, N.A., as depositary hereunder (the "Depositary"), and all holders from time to time of American Depositary Receipts issued hereunder ("ADRs") evidencing American Depositary Shares ("ADSs") representing deposited Shares (defined below).

W I T N E S S E T H

      WHEREAS, Shire Pharmaceuticals Group plc ("Shire plc")has undergone a Scheme of Arrangement pursuant to which a new listed holding company of the Shire plc and its subsidiary undertakings, was put in place through a Court approved scheme of arrangement under section 425 of the Companies Act 1985 (as amended);

      WHEREAS, Shire plc and the Depositary had entered into a deposit agreement dated as of March 28, 1998, as amended (the "Old Deposit Agreement") to provide for the deposit of ordinary shares of Shire plc and for the creation of American depositary shares representing such ordinary shares;

      WHEREAS, the Company and the Depositary desire that the terms of the ADRs issued hereunder initially be identical in all respects to those American depositary receipts issued under the Old Deposit Agreement until such time as this Deposit Agreement shall be amended and restated;

      NOW THEREFORE, in consideration of the premises, the parties hereto agree as follows:

      1. Certain Definitions.

      (a) " ADR Register " is defined in paragraph (3) of the form of ADR.

      (b) " ADRs " mean certificates evidencing ADSs substantially in the form of Exhibit A annexed hereto (the " form of ADR "). The form of ADR is hereby incorporated herein and made a part hereof; the provisions of the form of ADR shall be binding upon the parties hereto.

      (c) Subject to paragraph (13) of the form of ADR, each " ADS " evidenced by an ADR represents the right to receive three (3) Shares and a pro rata share in any other Deposited Securities.

      (d) " Custodian " means the agent or agents of the Depositary (singly or collectively, as the context requires) named as Custodian in the form of ADR and any additional or substitute Custodian appointed pursuant to Section 9.

      (e) " Delivery Order " is defined in Section 3.

      (f) " Deposited Securities " as of any time means all Shares at such time deposited under this Deposit Agreement and any and all other Shares, securities, property and cash at such

time held by the Depositary or the Custodian in respect or in lieu of such deposited Shares and other Shares, securities, property and cash.

      (g) " Holder " means the person or persons in whose name an ADR is registered on the ADR Register.

      (h) " Securities Act of 1933 " means the United States Securities Act of 1933, as from time to time amended.

      (i) " Securities Exchange Act of 1934 " means the United States Securities Exchange Act of 1934, as from time to time amended.

      (j) " Shares " mean the Ordinary Shares of the Company and shall include the rights to receive Shares specified in paragraph (1) of the form of ADR.

      (k) " Transfer Office " is defined in paragraph (3) of the form of ADR.

      (l) " Withdrawal Order " is defined in Section 6.

      2. ADR Certificates . ADRs shall be engraved, printed or otherwise reproduced at the discretion of the Depositary in accordance with its customary practices in its American depositary receipt business, or at the request of the Company typewritten and photocopied on plain or safety paper, and shall be substantially in the form set forth in the form of ADR, with such changes as may be required by the Depositary or the Company to comply with their obligations hereunder, any applicable law, regulation, usage or the requirements of any securities exchange or market upon which the ADSs primarily may be listed or traded or to indicate any special limitations or restrictions to which any particular ADRs are subject. ADRs may be issued in denominations of any number of ADSs. ADRs shall be executed by the Depositary by the manual or facsimile signature of a duly authorized officer of the Depositary. ADRs bearing the facsimile signature of anyone who was at the time of execution a duly authorized officer of the Depositary shall bind the Depositary, notwithstanding that such officer has ceased to hold such office prior to the delivery of such ADRs.

      3. Deposit of Shares . In connection with the deposit of Shares hereunder, the Depositary or the Custodian may require the following in form satisfactory to it: (a) a written order directing the Depositary to execute and deliver to, or upon the written order of, the person or persons designated in such order an ADR or ADRs evidencing the number of ADSs representing such deposited Shares (a "Delivery Order"); (b) proper endorsements or duly executed and stamped instruments of transfer in respect of such deposited Shares; (c) instruments assigning to the Custodian or its nominee any distribution on or in respect of such deposited Shares or indemnity therefor; and, (d) proxies entitling the Custodian to vote such deposited Shares. As soon as practicable after the Custodian receives Deposited Securities pursuant to any such deposit or pursuant to paragraph (10) or (13) of the form of ADR, the Custodian shall present such

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Deposited Securities for registration of transfer into the name of the Depositary or its nominee or the Custodian or its nominee, to the extent such registration is practicable, at the cost and expense of the person making such deposit (or for whose benefit such deposit is made) and shall obtain evidence satisfactory to it of such registration. Deposited Securities shall be held by the Custodian for the account and to the order of the Depositary at such place or places and in such manner as the Depositary shall determine. Deposited Securities may be delivered by the Custodian to any person only under the circumstances expressly contemplated in the Deposit Agreement.

      4. Issue of ADRs . After any such deposit of Shares, the Custodian shall notify the Depositary of such deposit and of the information contained in any related Delivery Order by letter, first class airmail postage prepaid, or, at the request, risk and expense of the person making the deposit, by cable, telex or facsimile transmission. After receiving such notice from the Custodian, the Depositary, subject to the Deposit Agreement, shall execute and deliver at the Transfer Office, to or upon the order of any person named in such notice, an ADR or ADRs registered as requested and evidencing the aggregate ADSs to which such person is entitled.

      5. Distributions on Deposited Securities . To the extent that the Depositary determines in its discretion that any distribution pursuant to paragraph (10) of the form of ADR is not practicable with respect to any Holder, the Depositary may make such distribution as it so deems practicable, including the distribution of foreign currency, securities or property (or appropriate documents evidencing the right to receive foreign currency, securities or property) or the retention thereof as Deposited Securities with respect to such Holder's ADRs (without liability for interest thereon or the investment thereof).

      6. Withdrawal of Deposited Securities . In connection with any surrender of an ADR for withdrawal of the Deposited Securities represented by the ADSs evidenced thereby, the Depositary may require proper endorsement in blank of such ADR (or duly executed instruments of transfer thereof in blank) and the Holder's written order directing the Depositary to cause the Deposited Securities represented by the ADSs evidenced by such ADR to be withdrawn and delivered to, or upon the written order of, any person designated in such order (a "Withdrawal Order"). Directions from the Depositary to the Custodian to deliver Deposited Securities shall be given by letter, first class airmail postage prepaid, or, at the request, risk and expense of the Holder, by cable, telex or facsimile transmission. Delivery of Deposited Securities may be made by the delivery of certificates (which, if required by law shall be properly endorsed or accompanied by properly executed instruments of transfer or, if such certificates may be registered, registered in the name of such Holder or as ordered by such Holder in any Withdrawal Order) or by such other means as the Depositary may deem practicable.

      7. Substitution of ADRs . The Depositary shall execute and deliver a new ADR of like tenor in exchange and substitution for any mutilated ADR upon cancellation thereof or in lieu of and in substitution for such destroyed, lost or stolen ADR, unless the Depositary has notice that such ADR has been acquired by a bona fide purchaser, upon the Holder thereof filing with the Depositary a request for such execution and delivery and a sufficient indemnity bond and

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satisfying any other reasonable requirements imposed by the Depositary.

      8. Cancellation and Destruction of ADRs . All ADRs surrendered to the Depositary shall be canceled by the Depositary. The Depositary is authorized to destroy ADRs so canceled in accordance with its customary practices.

      9. The Custodian . Any Custodian in acting hereunder shall be subject to the directions of the Depositary and shall be responsible solely to it. The Depositary may from time to time, after consultation with the Company if practicable, appoint one or more agents to act for it as Custodian hereunder in addition to or in lieu of the Custodian appointed hereunder. Each Custodian so appointed (other than JPMorgan Chase Bank, N.A.) shall give written notice to the Company and the Depositary accepting such appointment and agreeing to be bound by the applicable terms hereof. Any Custodian may resign from its duties hereunder by at least 30 days written notice to the Depositary. The Depositary may discharge any Custodian at any time upon notice to the Custodian being discharged. Courtesy copies of any such notice shall be provided to the Company. Any Custodian ceasing to act hereunder as Custodian shall deliver, upon the instruction of the Depositary, all Deposited Securities held by it to a Custodian so continuing to act.

      10. Co-Registrars and Co-Transfer Agents . The Depositary may appoint and remove (i) co-registrars to register ADRs and transfers, combinations and split-ups of ADRs and to countersign ADRs in accordance with the terms of any such appointment and (ii) co-transfer agents for the purpose of effecting transfers, combinations and split-ups of ADRs at designated transfer offices in addition to the Transfer Office on behalf of the Depositary. Each co-registrar or co-transfer agent (other than JPMorgan Chase Bank, N.A.) shall give notice in writing to the Company and the Depositary accepting such appointment and agreeing to be bound by the applicable terms of the Deposit Agreement.

      11. Lists of Holders . The Company shall have the right to inspect transfer records of the Depositary and its agents and the ADR Register, take copies thereof and require the Depositary and its agents to supply copies of such portions of such records as the Company may request. The Depositary or its agent shall furnish to the Company promptly upon the written request of the Company, a list of the names, addresses and holdings of ADSs by all Holders as of a date within seven days of the Depositary's receipt of such request.

      12. Depositary's Agents . The Depositary may perform its obligations under the Deposit Agreement through any agent appointed by it, provided that the Depositary shall notify the Company of such appointment and shall remain responsible for the performance of such obligations as if no agent were appointed.

      13. Successor Depositary . If the Depositary acting hereunder shall resign or be removed, the Company shall, unless it elects to terminate this Agreement in accordance with paragraph (17) of the form of ADR, use its best efforts to appoint a bank or trust company having an office in the Borough of Manhattan, The City of New York, as successor depositary hereunder. Every

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successor depositary shall execute and deliver to its predecessor and to the Company written acceptance of its appointment hereunder, and thereupon such successor depositary, without any further act or deed, shall become Depositary hereunder; but such predecessor, upon payment of all sums due it and on the written request of the Company, shall execute and deliver an instrument transferring to such successor all rights and powers of such predecessor hereunder and assigning all interest in the Deposited Securities to such successor, and shall deliver to such successor a copy of its records in respect of all outstanding ADRs issued hereunder and a list of the Holders. Any bank or trust company into or with which the Depositary may be merged or consolidated shall be the successor of the Depositary without the execution or filing of any document or any further act. Upon the appointment of any successor depositary hereunder, any agent of the Depositary then acting hereunder shall forthwith become such agent hereunder of such successor depositary and such successor depositary shall, on the written request of any such agent, execute and deliver to such agent any instruments necessary to give such agent authority as such agent hereunder of such successor depositary. Notwithstanding the foregoing, any appointment of a successor Depositary shall not relieve the predecessor Depositary or the Company from those obligations and liabilities to each other under Section 16 hereof which arose prior to the appointment of such successor Depositary. A predecessor Depositary shall not have any liability or incur any expense as a result of any action or inaction on the part of a successor Depositary.

      14. Reports . The Depositary shall make available for inspection by Holders at the Transfer Office any reports and communications received by the Company which are both (a) received by the Depositary as the holder of the Deposited Securities and (b) made generally available to the holders of such Deposited Securities by the Company. The Depositary shall also promptly send to the Holders copies of such reports when furnished by the Company. Any such reports and communications furnished to the Depositary by the Company shall be furnished in English. On or before the first date on which the Company gives notice, by publication or otherwise, of any meeting of holders of Shares or other Deposited Securities, or of any adjourned meeting of such holders, or the taking of any action by such holders other than at a meeting, the Company shall transmit to the Custodian and the Depositary a copy thereof in English in the form given or to be given, or made publicly available, to holders of Shares or other Deposited Securities. At the written request of the Company and upon receipt of a sufficient number of copies of such notices from the Company, the Depositary will arrange for the prompt mailing of copies of such notices to all Holders. In connection with any registration statement under the Securities Act of 1933 relating to the ADRs or with any undertaking contained therein, the Company and the Depositary shall each furnish to the other and to the United States Securities and Exchange Commission or any successor governmental agency such information as shall be required to make such filings or comply with such undertakings. The Company has delivered to the Depositary, the Custodian and any Transfer Office, a copy of all provisions of or governing the Shares and any other Deposited Securities issued by the Company or any affiliate of the Company and, promptly upon any change thereto, the Company shall deliver to the Depositary, the Custodian and any Transfer Office, a copy (in English or with an English translation) of such provisions as so changed. The Depositary and its agents may rely upon the Company's delivery thereof for all purposes of the Deposit Agreement.

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      15. Additional Shares . Neither the Company nor any company controlled by the Company shall issue additional Shares, rights to subscribe for Shares, securities convertible into or exchangeable for Shares or rights to subscribe for any such securities or shall deposit any Shares under this Deposit Agreement, except under circumstances complying in all respects with, and not in violation of, the Securities Act of 1933. The Company shall use its best efforts to ensure that any company controlling or under common control with the Company shall abide by the restrictions set forth in the preceding sentence. The Depositary will use reasonable efforts to comply with written instructions of the Company not to accept for deposit hereunder any Shares identified in such instructions at such times and under such circumstances as may reasonably be specified in such instructions in order to facilitate the Company's compliance with securities laws in the United States.

      16. Indemnification . (a) The Company shall indemnify, defend and save harmless each of the Depositary and its agents against any loss, liability or expense (including reasonable fees and expenses of counsel) that may arise out of (a) its acceptance and performance of its powers and duties in respect of the Deposit Agreement, except to the extent such loss, liability or expense is due to the negligence or bad faith of the Depositary or its agents, as the case may be, or (b) any offer or sale of ADRs, ADSs, Shares or other Deposited Securities or any registration statement under the Securities Act of 1933 in respect thereof filed by the Company (including any Form F-6 registration statement to which this Deposit Agreement has been, and may hereafter be, filed or incorporated by reference therein as an exhibit), except to the extent such loss, liability or expense arises out of information (or omissions from such information) relating to it furnished in writing to the Company by it expressly for use in any such registration statement. Each of the Depositary and its agents shall indemnify, defend and save harmless the Company against any loss, liability or expense incurred by the Company in respect of the Deposit Agreement to the extent such loss, liability or expense is due to the negligence or bad faith of such person. The obligations set forth in this Section 16 shall survive the termination of the Deposit Agreement and the succession or substitution of any indemnified person.

      (b) Any person seeking indemnification hereunder (an " indemnified person ") shall notify the person from whom it is seeking indemnification (the " indemnifying person ") of the commencement of any indemnifiable action or claim promptly after such indemnified person becomes aware of such commencement (provided that the failure to make such notification shall not affect such indemnified person's rights otherwise than under this Section 16 and shall only affect its rights hereunder to the extent such failure is prejudicial) and shall consult in good faith with the indemnifying person as to the conduct of the defense of such action or claim, which shall be reasonable in the circumstances. No indemnified person shall compromise or settle any indemnifiable action or claim without the prior written consent of the indemnifying person (which consent shall not be unreasonably withheld or delayed).

      (c) The obligations set forth in this Section 16 shall survive the termination of the Deposit Agreement and the succession or substitution of any indemnified person.

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      17. Notices . Notice to any Holder shall be deemed given when first mailed, first class postage prepaid, to the address of such Holder on the ADR Register or received by such Holder. Notice to the Depositary or the Company shall be deemed given when first received by it at the address or facsimile transmission number set forth in (a) or (b), respectively, or at such other address or facsimile transmission number as either may specify to the other by written notice:

      18. Miscellaneous . The Deposit Agreement is for the exclusive benefit of the Company, the Depositary, the Holders, and their respective successors hereunder, and shall not give any legal or equitable right, remedy or claim whatsoever to any other person. The Holders and owners of ADRs from time to time shall be parties to the Deposit Agreement and shall be bound by all of the provisions hereof. If any such provision is invalid, illegal or unenforceable in any respect, the remaining provisions shall in no way be affected thereby. The Deposit Agreement may be executed in any number of counterparts, each of which shall be deemed an original and all of which shall constitute one instrument.

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      IN WITNESS WHEREOF, SHIRE plc and JPMORGAN CHASE BANK, N.A. have duly executed this Deposit Agreement as of the day and year first above set forth and all holders of ADRs shall become parties hereto upon acceptance by them of ADRs issued in accordance with the terms hereof.

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EXHIBIT A
ANNEXED TO AND INCORPORATED IN
DEPOSIT AGREEMENT

[FORM OF FACE OF ADR]

THE RIGHT OF HOLDERS HEREOF TO DIRECT THE VOTING OF SHARES MAY BE RESTRICTED AS DESCRIBED IN PARAGRAPHS (6) AND (12) BELOW.

AMERICAN DEPOSITARY RECEIPT

evidencing

AMERICAN DEPOSITARY SHARES

representing

ORDINARY SHARES, NOMINAL VALUE 5P EACH

of

SHIRE plc

      (Incorporated under the
laws of England and Wales)

      JPMORGAN CHASE BANK, N.A., a national banking association organized under the laws of the United States, as depositary hereunder (the "Depositary"), hereby certifies that _______ is the registered owner (a "Holder") of _