EXECUTION COPY




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                      PREFERENCE SHARES GUARANTEE AGREEMENT



                              SHIRE FINANCE LIMITED







                         SHIRE PHARMACEUTICALS GROUP PLC

                                    GUARANTOR







                              THE BANK OF NEW YORK

                                GUARANTEE TRUSTEE




                         ------------------------------



                           Dated as of August 21, 2001


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<PAGE>


                             CROSS-REFERENCE TABLE(1)



                  Section of Trust Indenture Act                Section of
                       of 1939, as amended                       Guarantee

310(a)  ...................................................       4.01(a)
310(b) ....................................................    2.09, 4.01(c)
310(c) ....................................................    Inapplicable
311(a) ....................................................       2.02(b)
311(b) ....................................................       2.02(b)
311(c) ....................................................    Inapplicable
312(a) ....................................................       2.02(a)
312(b) ....................................................       2.02(b)
313 .......................................................        2.03
314(a) ....................................................        2.04
314(b) ....................................................    Inapplicable
314(c) ....................................................        2.05
314(d) ....................................................    Inapplicable
314(f) ....................................................    Inapplicable
315(a) ....................................................  3.01(c), 3.01(d)
315(b) ....................................................        2.07
315(c) ....................................................       3.01(c)
315(d) ....................................................       3.01(d)
316(a) ....................................................        2.08


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1    This Cross-Reference Table does not constitute part of the Guarantee and
     shall not affect the interpretation of any of its terms or provisions.



<PAGE>



                                TABLE OF CONTENTS
                                                                            PAGE




                                    ARTICLE 1
                         DEFINITIONS AND INTERPRETATION

SECTION 1.01. Definitions and Interpretation.................................1


                                    ARTICLE 2
                               TRUST INDENTURE ACT

SECTION 2.01.      Trust Indenture Act; Application..........................4
SECTION 2.02.      Lists of Holders of Securities............................4
SECTION 2.03.      Reports by the Guarantee Trustee..........................5
SECTION 2.04.      Periodic Reports to Guarantee Trustee.....................5
SECTION 2.05.      Evidence of Compliance with Conditions Precedent..........5
SECTION 2.06.      Events of Default; Waiver.................................5
SECTION 2.07.      Event of Default; Notice..................................5
SECTION 2.08.      Rights of Holders.........................................6
SECTION 2.09.      Conflicting Interests.....................................6


                                    ARTICLE 3
                 POWERS, DUTIES AND RIGHTS OF GUARANTEE TRUSTEE

SECTION 3.01. Powers, Duties and Rights of Guarantee Trustee.................6
SECTION 3.02. Certain Rights of Guarantee Trustee............................8
SECTION 3.03. Not Responsible for Recitals or Issuance of Guarantee.........10


                                    ARTICLE 4
                                GUARANTEE TRUSTEE

SECTION 4.01. Guarantee Trustee; Eligibility................................10
SECTION 4.02. Appointment, Removal and Resignation of Guarantee
                 Trustee....................................................11


                                    ARTICLE 5
                                    GUARANTEE

SECTION 5.01. Guarantee.....................................................11
SECTION 5.02. Waiver of Notice and Demand...................................12
SECTION 5.03. Obligations Not Affected......................................12
SECTION 5.04. Action Against Guarantor......................................13
SECTION 5.05. Independent Obligations.......................................13
SECTION 5.06. Subrogation...................................................13


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                                    ARTICLE 6
                                     RANKING
SECTION 6.01. Ranking.......................................................14



                                    ARTICLE 7
                         REPRESENTATIONS AND WARRANTIES;
                           AGREEMENTS OF THE GUARANTOR

SECTION 7.01 Representations and Warranties of the Guarantor................14
SECTION 7.02. Agreements of the Guarantor...................................14



                                    ARTICLE 8
                                   TERMINATION

SECTION 8.01. Termination...................................................17


                                    ARTICLE 9
                                 INDEMNIFICATION

SECTION 9.01. Exculpation...................................................17
SECTION 9.02. Indemnification...............................................17


                                   ARTICLE 10
                                  MISCELLANEOUS

SECTION 10.01. Successors and Assigns.......................................18
SECTION 10.02. Amendments...................................................18
SECTION 10.03. Judgment Currency Indemnity..................................18
SECTION 10.04. Assignment of the Guarantor..................................19
SECTION 10.05. Notices......................................................19
SECTION 10.06. Governing Law................................................20
SECTION 10.07. Jurisdiction and Service of Process..........................20


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<PAGE>


     This PREFERENCE SHARES GUARANTEE AGREEMENT (the "Guarantee") dated as of
August 21, 2001, is executed and delivered by Shire Pharmaceuticals Group plc, a
public limited company organized under the laws of England (the "Guarantor" or
the "Company"), and The Bank of New York, a New York banking corporation, as
trustee (the "Guarantee Trustee"), for the benefit of any Holders (as defined
herein) from time to time of the Preference Shares (as defined herein) of Shire
Finance Limited, an exempted limited company duly organized and existing under
the laws of the Cayman Islands (the "Issuer").

     WHEREAS, pursuant to an Indenture dated as of August 21, 2001 among the
Issuer, the Company and The Bank of New York, as trustee (the "Indenture"), the
Issuer is issuing on the date hereof 2.0% Guaranteed Convertible Senior Notes
Due 2011 (the "Securities") convertible into Exchangeable Redeemable Preference
Shares with a nominal value of $1 each (the "Preference Shares") in the capital
of the Issuer;

     WHEREAS, as incentive for the initial purchasers to purchase the
Securities, the Guarantor desires irrevocably and unconditionally to agree, to
the extent set forth herein, to pay to any subsequent Holders from time to time
of the Preference Shares the Guarantee Payments (as defined herein), to make
certain other payments and to give certain covenants, on the terms and
conditions set forth herein;

     NOW, THEREFORE, in consideration of the purchase by the initial purchasers
and any subsequent holder from time to time of Securities, which purchase the
Guarantor hereby agrees shall benefit the Guarantor, the Guarantor executes and
delivers this Guarantee for the benefit of any and all Holders and subsequent
Holders from time to time of the Preference Shares.


                                    ARTICLE 1
                         DEFINITIONS AND INTERPRETATION

     SECTION 1.01. Definitions and Interpretation. In this Guarantee, unless the
context otherwise requires:

          (a) capitalized terms used in this Guarantee but not defined in the
     preamble above have the respective meanings assigned to them in this
     Section 1.01;

          (b) Capitalized terms used in this Guarantee but not defined in the
     preamble above or in this Section 1.01 have the respective meanings
     assigned to them in the Indenture;

          (c) a term defined anywhere in this Guarantee has the same meaning
     throughout;

          (d) all references to "the Guarantee" or "this Guarantee" are to this
     Guarantee as modified, supplemented or amended from time to time;



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<PAGE>

          (e) all references in this Guarantee to Articles and Sections are to
     Articles and Sections of this Guarantee, unless otherwise specified; and

          (f) a reference to the singular includes the plural and vice versa.

     "ADR Depositary" means any depositary for the deposit of Ordinary Shares
against the issuance of ADRs evidencing ADSs representing such Ordinary Shares.

     "ADRs" has the meaning set forth in Section 7.02(d).

     "ADSs" means American depositary shares, each initially representing three
Ordinary Shares.

     "Affiliate" means, with respect to any specified person, any other person
that directly or indirectly controls or is controlled by, or is under common
control with, such specified person.

     "Articles" means the Amended and Restated Memorandum and Articles of
Association of the Issuer, as may be further amended and restated from time to
time.

     "Authorized Officer" of a Person means any Person that is authorized to
bind such Person.

     "Business Day" has the meaning set forth for such terms in the Indenture.

     "Company" has the meaning set forth in the first paragraph of this
Guarantee.

     "Conversion and Exchange Rights" means the right of each holder of
Securities to convert Securities into Preference Shares which shall be
exchanged, pursuant and subject to the Indenture, the terms of the Securities,
the Articles of the Issuer and this Guarantee, into Ordinary Shares or, at the
option of the Holder, ADSs, at any time up to and including August 14, 2011.

     "Corporate Trust Office" means the principal trust office of the Guarantee
Trustee at which, at any particular time, its corporate trust business shall be
principally administered, which office at the date hereof is located at 101
Barclay Street, Floor 21 West, New York, NY 10286, Attention: Corporate Trust
Administration.

     "Covered Person" means any Holder or beneficial owner of Preference Shares.

     "Dividend Payment Date" has the meaning specified for such term in the
Articles.

     "Dividend Period" has the meaning specified for such term in the Articles.

     "Dividend Rate" means a fixed rate per annum of 2,000% of the nominal value
of each Preference Share.

     "Dividends" means cash income dividends and other distributions with
respect to the Preference Shares.



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<PAGE>

     "Event of Default" means a default by the Guarantor on any of its payment
or other obligations under this Guarantee.

     "Guarantee Payments" has the meaning set forth in Section 5.01.

     "Guarantee Trustee" means The Bank of New York, a New York banking
corporation, until a Successor Guarantee Trustee has been appointed and has
accepted such appointment pursuant to the terms of this Guarantee by executing a
counterpart hereof and becoming a party hereto and thereafter means each such
Successor Guarantee Trustee.

     "Guarantor" has the meaning set forth in the first paragraph of this
Guarantee.

     "Holder" means a Person in whose name a Preference Share is registered on
the books and records of the Issuer; provided that solely for the purposes of
determining whether the Holders of the requisite liquidation preference of
Preference Share have given any request, notice, consent or waiver with respect
to any matter provided for in this Agreement, "Holder" shall not include the
Guarantor or any Affiliate of the Guarantor.

     "Indemnified Person" means the Guarantee Trustee, any Affiliate of the
Guarantee Trustee, or any officer, director, shareholder, member, partner,
employee, representative, nominee, custodian or agent of the Guarantee Trustee.

     "Indenture" has the meaning set forth in the first recital to this
Guarantee.

     "Investment Company Act" means the U.S. Investment Company Act of 1940, as
amended from time to time, or any successor legislation.

     "Issuer" has the meaning set forth in the first paragraph of this
Guarantee.

     "Majority" means, except as provided by the Trust Indenture Act, a vote by
Holder(s) of Preference Shares, voting separately as a class, of more than 50%
of the liquidation preference of all Preference Shares.

     "Officers' Certificate" means, with respect to any Person, a certificate
signed by two Authorized Officers of such Person.

     "Ordinary Shares" means the ordinary shares, nominal value U.K. five pence
per share, of the Company at the date of this instrument as originally executed.
Shares issuable on conversion of Preference Shares shall include only Ordinary
Shares or shares of any class or classes of ordinary shares resulting from any
reclassification or reclassifications thereof; provided, however, that if at any
time there shall be more than one such resulting class, the shares so issuable
on conversion of Preference Shares shall include shares of all such classes, and
the shares of each such class then so issuable shall be substantially in the
proportion which the total number of shares of such class resulting from all
such reclassifications bears to the total number of shares of all such classes
resulting from all such reclassifications.

     "Preference Shares" has the meaning set forth in the first recital to this
Guarantee.



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<PAGE>

     "Person" means a legal person, including any individual, corporation,
estate, partnership, joint venture, association, joint stock company, limited
liability company, trust, unincorporated association, or government or any
agency or political subdivision thereof or any other entity of whatever nature.

     "Redemption Price" has the meaning set forth in Section 5.01(ii).

     "Register" has the meaning set forth in Section 2.02.

     "Responsible Officer" means, with respect to the Guarantee Trustee, any
officer within the Corporate Trust Office of the Guarantee Trustee, including
any vice president, any assistant vice president, any secretary, any assistant
secretary, the treasurer, any assistant treasurer or other officer of the
Guarantee Trustee customarily performing functions similar to those performed by
any of the above designated officers and also means, with respect to a
particular corporate trust matter, any other officer to whom such matter is
referred because of that officer's knowledge of and familiarity with the
particular subject.

     "Securities Act" means the U.S. Securities Act of 1933, as amended from
time to time, or any successor legislation.

     "Successor Guarantee Trustee" means a successor Guarantee Trustee
possessing the qualifications to act as Guarantee Trustee under Section 4.01.

     "Trust Indenture Act" means the U.S. Trust Indenture Act of 1939, as
amended from time to time, or any successor legislation.


                                    ARTICLE 2
                               TRUST INDENTURE ACT

     SECTION 2.01. Trust Indenture Act; Application. (a) This Guarantee is
subject to the provisions of the Trust Indenture Act that are required to be
part of this Guarantee and shall, to the extent applicable, be governed by such
provisions. A term defined in the Trust Indenture Act has the same meaning when
used in this Guarantee, unless otherwise defined in this Guarantee or unless the
context otherwise requires.

     (b) If and to the extent that any provision of this Guarantee limits,
qualifies or conflicts with the duties imposed by Sections 310 to 317,
inclusive, of the Trust Indenture Act, such imposed duties shall control.

     SECTION 2.02. Lists of Holders of Securities. (a) The Guarantee Trustee
shall preserve in as current a form as is reasonably practicable the most recent
list available to it of the names and addresses of Holders of Preference Shares
(the "Register") and shall at all times keep the Register outside the United
Kingdom. If the Guarantee Trustee is not the keeper of the Register, the
Guarantor shall furnish to the Guarantee Trustee (i) within 14 days after each
record date for payment of Dividends and (ii) at any other time within 30 days
of receipt by the Guarantor of a



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<PAGE>

written request, a list, in such form and as of such date as the Guarantee
Trustee may reasonably require, containing all the information in the possession
or control of the keeper of the Register, the Guarantor or any of its paying
agents other than the Guarantee Trustee as to the names and addresses of Holders
of Preference Shares.

     (b) The Guarantee Trustee shall comply with its obligations under Sections
311(a), 311(b) and 312(b) of the Trust Indenture Act.

     SECTION 2.03. Reports by the Guarantee Trustee. Within 60 days after May 15
of each year, the Guarantee Trustee shall provide to the Holders of the
Preference Shares such reports as are required by Section 313 of the Trust
Indenture Act, if any, in the form and in the manner provided by Section 313 of
the Trust Indenture Act. The Guarantee Trustee shall also comply with the
requirements of Section 313(d) of the Trust Indenture Act.

     SECTION 2.04. Periodic Reports to Guarantee Trustee. The Guarantor shall
provide to the Guarantee Trustee such documents, reports and information as
required by Section 314 (if any) and the compliance certificate required by
Section 314 of the Trust Indenture Act in the form, in the manner and at the
times required by Section 314 of the Trust Indenture Act. Delivery of such
reports, information and documents to the Guarantee Trustee is for informational
purposes only and the Guarantee Trustee's receipt of such shall not constitute
constructive notice of any information contained therein or determinable from
information contained therein, including the Guarantor's compliance with any of
its covenants hereunder (as to which the Guarantee Trustee is entitled to rely
exclusively on Officers' Certificates).

     SECTION 2.05. Evidence of Compliance with Conditions Precedent. The
Guarantor shall provide to the Guarantee Trustee such evidence of compliance
with any conditions precedent, if any, provided for in this Guarantee that
relate to any of the matters set forth in Section 314(c) of the Trust Indenture
Act. Any certificate or opinion required to be given by an officer pursuant to
Section 314(c)(1) may be given in the form of an Officers' Certificate and shall
include:

          (a) a statement that each officer signing the Officers' Certificate
     has read the covenant or condition and the definition relating thereto;

          (b) a brief statement of the nature and scope of the examination or
     investigation undertaken by each officer in rendering the Officers'
     Certificate;

          (c) a statement that each such officer has made such examination or
     investigation as, in such officer's opinion, is necessary to enable such
     officer to express an informed opinion as to whether or not such covenant
     or condition has been complied with; and

          (d) a statement as to whether, in the opinion of each such officer,
     such condition or covenant has been complied with.



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<PAGE>

     SECTION 2.06. Events of Default; Waiver. The Holders of a Majority of the
Preference Shares may, by vote, on behalf of the Holders of all of the
Preference Shares, waive any past Event of Default and its consequences except
an Event of Default in respect of a covenant or provision hereof which cannot be
modified or amended without the consent of each Holder of Preference Shares.
Upon such waiver, any such Event of Default shall cease to exist, and any Event
of Default arising therefrom shall be deemed to have been cured, for every
purpose of this Guarantee, but no such waiver shall extend to any subsequent or
other default or Event of Default or impair any right consequent thereon.

     SECTION 2.07. Event of Default; Notice. (a) The Guarantee Trustee shall,
within 90 days after the occurrence of an Event of Default, transmit by mail,
first class postage prepaid, to the Holders of the Preference Shares, notices of
all Events of Default actually known to a Responsible Officer of the Guarantee
Trustee, unless such defaults have been cured before the giving of such notice,
provided, that, the Guarantee Trustee shall be protected in withholding such
notice if and so long as the board of directors, the executive committee or a
trust committee of directors and/or a Responsible Officer of the Guarantee
Trustee in good faith determines that the withholding of such notice is in the
interests of the Holders of the Preference Shares.

     (b) The Guarantee Trustee shall not be deemed to have knowledge of any
Event of Default unless a Responsible Officer of the Guarantee Trustee shall
have received written notice, or a Responsible Officer of the Guarantee Trustee
charged with the administration of the Guarantee shall have obtained actual
knowledge, of such Event of Default.

     SECTION 2.08. Rights of Holders. (a) The Holders of a Majority of the
Preference Shares have the right to direct the time, method and place of
conducting any proceeding for any remedy available to the Guarantee Trustee in
respect of this Guarantee or exercising any trust or power conferred upon the
Guarantee Trustee under this Guarantee.

     (b) If the Guarantee Trustee fails to enforce its rights under the
Guarantee after a Holder of Preference Shares has made a written request, such
Holder of Preference Shares may institute a legal proceeding directly against
the Guarantor to enforce the Guarantee Trustee's rights under Article 5 or
Article 7 of this Guarantee, without first instituting a legal proceeding
against the Issuer, the Guarantee Trustee or any other person or entity.
Notwithstanding the foregoing, if the Guarantor has failed to make a Guarantee
Payment, a Holder of Preference Shares may directly institute a proceeding in
such Holder's own name against the Guarantor for enforcement of Article 5 of
this Guarantee for such payment.

     (c) For so long as any Preference Shares remain outstanding, a Holder of
Preference Shares may exercise directly any right or power of a Holder of
Preference Shares under this Section 2.08.

     (d) The guarantee herein is a guarantee of payment under the Preference
Shares. As a result, in no event shall the rights to take remedial action under
this Guarantee result in any Holder of Preference Shares receiving any amount in
excess of the amounts due to such Holder in accordance with the terms of the
Articles and the Preference Shares, or receiving any amount due and payable to
such Holder as a Holder of Preference Shares sooner than the time at which



                                       6
<PAGE>

such Holder is entitled to receive such amounts in accordance with the terms of
the Indenture, the Securities, the Articles and the Preference Shares.

     SECTION 2.09. Conflicting Interests. The Articles shall be deemed to be
specifically described in this Guarantee for the purposes of clause (i) of the
first proviso contained in Section 310(b) of the Trust Indenture Act.


                                    ARTICLE 3
                 POWERS, DUTIES AND RIGHTS OF GUARANTEE TRUSTEE

     SECTION 3.01. Powers, Duties and Rights of Guarantee Trustee. (a) This
Guarantee shall be held by the Guarantee Trustee for the benefit of the Holders
of the Preference Shares, and the Guarantee Trustee shall not transfer this
Guarantee to any Person except a Holder of Preference Shares exercising his or
her rights pursuant to Section 2.08(b) or to a Successor Guarantee Trustee on
acceptance by such Successor Guarantee Trustee of its appointment to act as
Successor Guarantee Trustee. The right, title and interest of the Guarantee
Trustee shall automatically vest in any Successor Guarantee Trustee, and such
vesting and cessation of title shall be effective whether or not conveyancing
documents have been executed and delivered pursuant to the appointment of such
Successor Guarantee Trustee.

     (b) If an Event of Default actually known to a Responsible Officer of the
Guarantee Trustee has occurred and is continuing, the Guarantee Trustee shall
enforce this Guarantee for the benefit of the Holders of the Preference Shares.

     (c) The Guarantee Trustee, before the occurrence of any Event of Default
and after the curing or waiver of all Events of Default that may have occurred,
shall undertake to perform only such duties as are specifically set forth in
this Guarantee, and no implied covenants shall be read into this Guarantee
against the Guarantee Trustee. In case an Event of Default has occurred (that
has not been cured or waived pursuant to Section 2.06 and is actually known to a
Responsible Officer of the Guarantee Trustee), the Guarantee Trustee shall
exercise such of the rights and powers vested in it by this Guarantee, and use
the same degree of care and skill in its exercise thereof, as a prudent person
would exercise or use under the circumstances in the conduct of his or her own
affairs.

     (d) No provision of this Guarantee shall be construed to relieve the
Guarantee Trustee from liability for its own negligent action, its own negligent
failure to act, or its own willful misconduct, except that:

          (i) Prior to the occurrence of any Event of Default and after the
     curing or waiving of all such Events of Default that may have occurred:

               (A) the duties and obligations of the Guarantee Trustee shall be
          determined solely by the express provisions of this Guarantee, and the
          Guarantee Trustee shall not be liable except for the performance of
          such duties and obligations as are specifically set forth in this
          Guarantee, and no implied



                                       7
<PAGE>

          covenants or obligations shall be read into this Guarantee against the
          Guarantee Trustee; and

               (B) in the absence of bad faith on the part of the Guarantee
          Trustee, the Guarantee Trustee may conclusively rely, as to the truth
          of the statements and the correctness of the opinions expressed
          therein, upon any certificates or opinions furnished to the Guarantee
          Trustee and conforming to the requirements of this Guarantee; but in
          the case of any such certificates or opinions that by any provision
          hereof are specifically required to be furnished to the Guarantee
          Trustee, the Guarantee Trustee shall be under a duty to examine the
          same to determine whether or not they conform to the requirements of
          this Guarantee (but need not confirm or investigate the accuracy of
          any mathematical calculations or other facts stated therein);

          (ii) The Guarantee Trustee shall not be liable for any error of
     judgment made in good faith by a Responsible Officer of the Guarantee
     Trustee, unless it shall be proved that the Guarantee Trustee was negligent
     in ascertaining the pertinent facts upon which such judgment was made;

          (iii) The Guarantee Trustee shall not be liable with respect to any
     action taken or omitted to be taken by it in good faith in accordance with
     the direction of the Holders of a Majority of the Preference Shares
     relating to the time, method and place of conducting any proceeding for any
     remedy available to the Guarantee Trustee, or the exercise of any trust or
     power conferred upon the Guarantee Trustee under this Guarantee; and

          (iv) No provision of this Guarantee shall require the Guarantee
     Trustee to expend or risk its own funds or otherwise incur personal
     financial liability in the performance of any of its duties or in the
     exercise of any of its rights or powers, if the Guarantee Trustee shall
     have reasonable grounds for believing that the repayment of such funds or
     liability, or indemnity, satisfactory to the Guarantee Trustee, against
     such expense, risk or liability, is not assured to it under the terms of
     this Guarantee.

     SECTION 3.02. Certain Rights of Guarantee Trustee. (a) Subject to the
provisions of Section 3.01:

          (i) The Guarantee Trustee may conclusively rely, and shall be fully
     protected in acting or refraining from acting upon, any resolution,
     certificate, statement, instrument, opinion, report, notice, request,
     direction, consent, order, bond, debenture, note, other evidence of
     indebtedness or other paper or document (whether in its original or
     facsimile form) believed by it to be genuine and to have been signed, sent
     or presented by the proper party or parties.

          (ii) Any direction or act of the Guarantor contemplated by this
     Guarantee shall be sufficiently evidenced by an Officers' Certificate.



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<PAGE>

          (iii) Whenever, in the administration of this Guarantee, the Guarantee
     Trustee shall deem it desirable that a matter be proved or established
     before taking, suffering or omitting any action hereunder, the Guarantee
     Trustee (unless other evidence is herein specifically prescribed) may, in
     the absence of bad faith on its part, request and conclusively rely upon an
     Officers' Certificate which, upon receipt of such request, shall be
     promptly delivered by the Guarantor.

          (iv) The Guarantee Trustee shall have no duty to see to any recording,
     filing or registration of any instrument (or any rerecording, refiling or
     registration thereof).

          (v) The Guarantee Trustee may consult with counsel of its selection,
     and the advice or opinion of such counsel with respect to legal matters
     shall be full and complete authorization and protection in respect of any
     action taken, suffered or omitted by it hereunder in good faith and in
     accordance with such advice or opinion. Such counsel may be counsel to the
     Guarantor or any of its Affiliates and may include any of its employees.
     The Guarantee Trustee shall have the right at any time to seek instructions
     concerning the administration of this Guarantee from any court of competent
     jurisdiction.

          (vi) The Guarantee Trustee shall be under no obligation to exercise
     any of the rights or powers vested in it by this Guarantee at the request
     or direction of any Holder, unless such Holder shall have provided to the
     Guarantee Trustee such security and indemnity, satisfactory to the
     Guarantee Trustee, against the costs, expenses (including attorneys' fees
     and expenses and the expenses of the Guarantee Trustee's agents, nominees
     or custodians) and liabilities that might be incurred by it in complying
     with such request or direction, including such reasonable advances as may
     be requested by the Guarantee Trustee; provided, however, that nothing
     contained in this Section 3.02(a)(vi) shall be taken to relieve the
     Guarantee Trustee, upon the occurrence of an Event of Default, of its
     obligation to exercise the rights and powers vested in it by this
     Guarantee.

          (vii) The Guarantee Trustee shall not be bound to make any
     investigation into the facts or matters stated in any resolution,
     certificate, statement, instrument, opinion, report, notice, request,
     direction, consent, order, bond, debenture, note, other evidence of
     indebtedness or other paper or document, but the Guarantee Trustee, in its
     discretion, may make such further inquiry or investigation into such facts
     or matters as it may see fit but shall incur no liability or additional
     liability of any kind by reason of such inquiry or investigation.

          (viii) The Guarantee Trustee may execute any of the trusts or powers
     hereunder or perform any duties hereunder either directly or by or through
     agents, nominees, custodians or attorneys, and the Guarantee Trustee shall
     not be responsible for any misconduct or negligence on the part of any
     agent or attorney appointed with due care by it hereunder.

          (ix) Any action taken by the Guarantee Trustee or its agents hereunder
     shall bind the Holders of the Preference Shares, and the signature of the
     Guarantee Trustee or its agents alone shall be sufficient and effective to
     perform any such action. No third



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<PAGE>

     party shall be required to inquire as to the authority of the Guarantee
     Trustee to so act or as to its compliance with any of the terms and
     provisions of this Guarantee, both of which shall be conclusively evidenced
     by the Guarantee Trustee or its agent taking such action.

          (x) Whenever in the administration of this Guarantee the Guarantee
     Trustee shall deem it desirable to receive instructions with respect to
     enforcing any remedy or right or taking any other action hereunder, the
     Guarantee Trustee (i) may request written instructions from the Holders of
     a Majority of the Preference Shares, (ii) may refrain from enforcing such
     remedy or right or taking such other action until such written instructions
     are received and (iii) shall be protected in conclusively relying on or
     acting in accordance with such written instructions.

          (xi) The Guarantee Trustee shall not be liable for any action taken,
     suffered, or omitted to be taken by it in good faith, without negligence,
     and reasonably believed by it to be authorized or within the discretion or
     rights or powers conferred upon it by this Guarantee.

     (b) No provision of this Guarantee shall be deemed to impose any duty or
obligation on the Guarantee Trustee to perform any act or acts or exercise any
right, power, duty or obligation conferred or imposed on it in any jurisdiction
in which it shall be illegal, or in which the Guarantee Trustee shall be
unqualified or incompetent in accordance with applicable law, to perform any
such act or acts or to exercise any such right, power, duty or obligation. No
permissive power or authority available to the Guarantee Trustee shall be
construed to be a duty.

     SECTION 3.03. Not Responsible for Recitals or Issuance of Guarantee. The
recitals contained in this Guarantee shall be taken as the statements of the
Guarantor, and the Guarantee Trustee does not assume any responsibility for
their correctness. The Guarantee Trustee makes no representation as to the
validity or sufficiency of this Guarantee.


                                    ARTICLE 4
                                GUARANTEE TRUSTEE

     SECTION 4.01. Guarantee Trustee; Eligibility. (a) There shall at all times
be a Guarantee Trustee which shall:

          (i) not be an Affiliate of the Guarantor; and

          (ii) be a corporation organized and doing business under the laws of
     the United States of America or any State thereof or of the District of
     Columbia, or a corporation or Person permitted by the Securities and
     Exchange Commission to act as an institutional trustee under the Trust
     Indenture Act, authorized under such laws to exercise corporate trust
     powers, having a combined capital and surplus of at least 50 million U.S.
     dollars ($50,000,000), and subject to supervision or examination by U.S.
     federal or State authority, in good standing and having an office or agent
     in the Borough of Manhattan, The City of New York. If such corporation
     publishes reports of condition at least



                                       10
<PAGE>

     annually, pursuant to law or to the requirements of the supervising or
     examining authority referred to above, then, for the purposes of this
     Section 4.01(a)(ii), the combined capital and surplus of such corporation
     shall be deemed to be its combined capital and surplus as set forth in its
     most recent report of condition so published.

     (b)If at any time the Guarantee Trustee shall cease to be eligible to so
act under Section 4.01(a), the Guarantee Trustee shall immediately resign in the
manner and with the effect set out in Section 4.02(c).

     (c) If the Guarantee Trustee has or shall acquire any "conflicting
interest" within the meaning of Section 310(b) of the Trust Indenture Act, the
Guarantee Trustee and Guarantor shall in all respects comply with the provisions
of Section 310(b) of the Trust Indenture Act.

     (d) The Guarantee Trustee represents and warrants that:

          (i) the Guarantee Trustee is a New York banking corporation with trust
     powers, duly organized, validly existing and in good standing under the
     laws of the State of New York, with trust power and authority to execute
     and deliver, and to carry out and perform its obligations under, this
     Guarantee; and

          (ii) the execution, delivery and performance by the Guarantee Trustee
     of this Guarantee has been duly authorized by all necessary corporate
     action on the part of the Guarantee Trustee. This Guarantee has been duly
     executed and delivered by the Guarantee Trustee.

     SECTION 4.02. Appointment, Removal and Resignation of Guarantee Trustee.
(a) Subject to Section 4.02(b), the Guarantee Trustee may be appointed or
removed without cause at any time by the Guarantor (i) except during an Event of
Default and (ii) so long as the Issuer shall not be in default in the payment of
amounts due and payable under the Preference Shares.

     (b) The Guarantee Trustee shall not be removed in accordance with Section
4.02(a) until a Successor Guarantee Trustee has been appointed and has accepted
such appointment by written instrument executed by such Successor Guarantee
Trustee and delivered to the Guarantor.

     (c) The Guarantee Trustee appointed to office shall hold office until a
Successor Guarantee Trustee shall have been appointed or until its removal or
resignation. The Guarantee Trustee may resign from office (without need for
prior or subsequent accounting) by an instrument in writing executed by the
Guarantee Trustee and delivered to the Guarantor, which resignation shall not
take effect until a Successor Guarantee Trustee has been appointed and has
accepted such appointment by instrument in writing executed by such Successor
Guarantee Trustee and delivered to the Guarantor and the resigning Guarantee
Trustee.

     (d) If no Successor Guarantee Trustee shall have been appointed and
accepted appointment as provided in this Section 4.02 within 60 days after
delivery of an instrument of removal or resignation, the Guarantee Trustee
resigning or being removed may petition, at the



                                       11
<PAGE>

expense of the Guarantor, any court of competent jurisdiction for appointment of
a Successor Guarantee Trustee. Such court may thereupon, after prescribing such
notice, if any, as it may deem proper, appoint a Successor Guarantee Trustee.

     (e) No Guarantee Trustee shall be liable for the acts or omissions to act
of any Successor Guarantee Trustee.

     (f) Upon termination of this Guarantee or removal or resignation of the
Guarantee Trustee pursuant to this Section 4.02, and before the appointment of
any Successor Guarantee Trustee, the Guarantor shall pay to the Guarantee
Trustee all amounts to which it is entitled to the date of such termination,
removal or resignation.


                                    ARTICLE 5
                                    GUARANTEE

     SECTION 5.01. Guarantee. (a) The Guarantor irrevocably and unconditionally
agrees, subject to the limitations set forth in this Guarantee, the full and
punctual payment to each Holder from time to time, whether such rights under
this Guarantee are asserted by the Guarantee Trustee or directly by any such
Holder (without duplication of amounts theretofore paid by the Issuer or the
Guarantor), if, as and when due, regardless of any defense, right of setoff or
counterclaim that the Issuer may have or assert (other than the defense of
payment) of the following:

          (i) any due but unpaid Dividends on any Preference Shares held by such
     Holder;

          (ii) any amounts due in respect of a Preference Share (in accordance
     with the terms of the Articles) but unpaid upon exercise by a Holder of its
     right to require redemption of such Preference Share or in respect of a
     Preference Share otherwise due for redemption (the "Redemption Price"); and

          (iii) the amount payable to a Holder in respect of a Preference Share
     upon any dissolution, liquidation or winding up of the Issuer;

(collectively, the "Guarantee Payments").

     (b) The guarantee under this Section 5.1 shall extend equally to all
Dividends, redemption monies, liquidation payments and other amounts expressed
to be payable in respect of any Preference Share that shall not have been issued
as required by the terms of the Securities and of the Indenture but which would
have been payable on such Preference Share had the same been issued when so
required.

     (c) The Guarantee Payments are payable hereunder whether or not the Issuer
had legally available funds for the making of a Dividend, a redemption payment
or a liquidation payment, as applicable.



                                       12
<PAGE>

     (d) All Guarantee Payments shall include interest accrued on such Guarantee
Payments, at a rate of 2.00 per annum, from the date of the claim asserted under
this Guarantee relating to such Guarantee Payments through the date of payment
of or the date full payment is offered on such claim.

     (e) The Guarantor's obligation to make any of the payments listed in (i)
through (iii) in Section 5.01(a) above may be satisfied by direct payment of the
required amounts by the Guarantor to the Holders or by causing the Issuer to pay
such amounts to the Holders.

     SECTION 5.02. Waiver of Notice and Demand. The Guarantor hereby waives
notice of acceptance of this Guarantee and of any liability to which it applies
or may apply, presentment, demand for payment, any right to require a proceeding
first against the Issuer or any other Person before proceeding against the
Guarantor, protest, notice of nonpayment, notice of dishonor, notice of
redemption and all other notices and demands (in each case in respect of
Guarantee Payments only).

     SECTION 5.03. Obligations Not Affected. The obligations, covenants,
agreements and duties of the Guarantor under this Guarantee shall in no way be
affected or impaired by reason of the happening from time to time of any of the
following:

          (a) the release or waiver, by operation of law or otherwise, of the
     performance or observance by the Issuer of any express or implied
     agreement, covenant, term or condition relating to the Preference Shares to
     be performed or observed by the Issuer;

          (b) the extension of time for the payment by the Issuer of all or any
     portion of the Dividends, Redemption Price, liquidation preference or any
     other sums payable under the terms of the Preference Shares or the
     extension of time for the performance of any other obligation under,
     arising out of; or in connection with, the Preference Shares; provided that
     nothing in this Guarantee shall affect or impair any valid extension;

          (c) any failure, omission, delay or lack of diligence on the part of
     the Holders to enforce, assert or exercise any right, privilege, power or
     remedy conferred on the Holders pursuant to the terms of the Preference
     Shares, or any action on the part of the Issuer granting indulgence or
     extension of any kind;

          (d) the voluntary or involuntary liquidation, dissolution, sale of any
     collateral, receivership, insolvency, bankruptcy, assignment for the
     benefit of creditors, reorganization, arrangement, composition or
     readjustment of debt of, or other similar proceedings affecting, the Issuer
     or any of the assets of the Issuer;

          (e) any invalidity of, or defect or deficiency in, the Preference
     Shares or any failure by or on behalf of the Issuer or by the Issuer in
     general meeting to declare or approve Dividend, redemption or liquidation
     payments or other amounts expressed to be payable in respect of the
     Preference Shares;



                                       13
<PAGE>

          (f) the settlement or compromise of any obligation guaranteed hereby
     or hereby incurred;

          (g) the unavailability to the Issuer under Cayman Islands law of
     legally available funds to make payments due on the Preference Shares or
     any other prohibition under applicable law of payments on the Preference
     Shares; or

          (h) any other circumstance whatsoever that might otherwise constitute
     a legal or equitable discharge or defense of a guarantor, it being the
     intent of this Section 5.03 that the obligations of the Guarantor under
     this Article 5 shall be absolute and unconditional under any and all
     circumstances.

     There shall be no obligation of the Holders to give notice to, or obtain
consent of, the Guarantor with respect to the happening of any of the foregoing.

     SECTION 5.04. Action Against Guarantor. In respect of Guarantee Payments
only, the Guarantor waives any right or remedy to require that any action be
brought first against the Issuer or any other person or entity before proceeding
directly against the Guarantor.

     SECTION 5.05. Independent Obligations. The Guarantor acknowledges that its
obligations hereunder are independent of the obligations of the Issuer with
respect to the Preference Shares, and that the Guarantor shall be liable as
principal and as debtor hereunder to make Guarantee Payments pursuant to the
terms of this Guarantee notwithstanding the occurrence of any event referred to
in subsections (a) through (h), inclusive, of Section 5.03 hereof.

     SECTION 5.06. Subrogation. Upon making any payment pursuant to Section
5.01, the Guarantor shall be subrogated to the rights of the payee against the
Issuer with respect to such payment; provided, however, that the Guarantor shall
not enforce any payment by way of subrogation if any Preference Shares are
outstanding.


                                    ARTICLE 6
                                     RANKING

     SECTION 6.01. Ranking. The guarantee under Section 5.1 constitutes a
direct, unconditional and unsecured obligation of the Guarantor and will rank at
least equally with all other unsecured and unsubordinated obligations of the
Guarantor (including unsecured and unsubordinated guarantees by the Guarantor of
indebtedness of others), subject in the event of insolvency, to laws of general
applicability relating to or affecting creditors' rights


                                    ARTICLE 7
           REPRESENTATIONS AND WARRANTIES; AGREEMENTS OF THE GUARANTOR

     SECTION 7.01 Representations and Warranties of the Guarantor. The Guarantor
represents and warrants that:


                                       14
<PAGE>


          (a) The Guarantor is duly organized and validly existing under the
     laws of England and Wales, with power and authority to execute and deliver,
     and to carry out and perform its obligations under, this Guarantee; and

          (b) The execution, delivery and performance by the Guarantor of this
     Guarantee has been duly authorized by all necessary corporate action on the
     part of the Guarantor. This Guarantee has been duly executed and delivered
     by the Guarantor.

     SECTION 7.02. Agreements of the Guarantor. (a) The Guarantor hereby agrees:

          (i) that, in the event of failure of the Issuer to perform any of its
     obligations or to enforce when due any of the rights of the Issuer in
     respect of the exercise of any Conversion and Exchange Rights, the issue of
     any Preference Shares on any such exercise and the exchange of Preference
     Shares for Ordinary Shares or ADSs pursuant to the exercise of Conversion
     and Exchange Rights, in each case in accordance with the Articles and as
     referred to in the terms of the Securities and the Indenture, the Guarantor
     will procure the performance by the Issuer of all such obligations and the
     enforcement by the Issuer of all such rights:

          (ii) not to alter its obligation pursuant to a bilateral contract
     between the Issuer and the Guarantor to issue Ordinary Shares or ADSs to
     holders of Preference Shares in order that the Issuer might meet its
     exchange obligations in respect of the Preference Shares in accordance with
     the Articles; and

          (iii) that, while any Security remains Outstanding, it will not
     consent to, and will procure that the Issuer will not make, any amendment
     to Article 9 of the Articles which would vary, abrogate or modify the
     rights attaching to the Preference Shares save with (a) the consent of the
     Trustee or (b) (1) the written consent of the holders of not less than a
     majority in principal amount of the Outstanding Securities by the Act of
     said holders delivered to the Issuer, the Guarantor and the Trustee; or (2)
     by the adoption of a resolution, at a meeting of holders of the Outstanding
     Securities at which a quorum is present, by the holders of a majority in
     principal amount of the Outstanding Securities represented at such meeting,
     provided, however, that the consent or affirmative vote of the holder of
     each Outstanding Security adversely affected shall be required before any
     amendment is made to Article 9 of the Articles which is adverse to the
     holders of the Securities, and provided further that no consent of the
     Trustee nor consent or affirmative vote of any holder of Securities shall
     be required in relation to any amendment which (i) does not adversely
     affect the interests of any holder of Securities or (ii) is to cure any
     ambiguity, omission or defect or to correct or supplement any provision of
     Article 9 of the Articles which may be inconsistent with any other
     provision of the Articles or which is otherwise defective, or to make any
     other provisions with respect to matters arising under the Articles as the
     Issuer, the Guarantor and the Trustee may deem necessary or desirable, in
     each case which does not adversely affect the interests of the holders of
     the Securities.



                                       15
<PAGE>

     (b) The Guarantor, for so long as any Securities remain outstanding shall
use its reasonable efforts to ensure that the Issuer will not be an "investment
company" within the meaning of the Investment Company Act or a Passive Foreign
Investment Company ("PFIC") within the meaning of Section 1297 of the United
States Internal Revenue Code of 1986, as amended.

     (c) The Guarantor agrees to use all reasonable efforts to ensure that all
corporate steps, including obtaining shareholder approvals if necessary, have
been taken for the allotment and issue of the Ordinary Shares or ADSs, free of
pre-emptive rights upon the exercise of Conversion and Exchange Rights;

     (d) The Guarantor agrees to pay all stamp, stamp duty reserve or other
issuance or documentary taxes or duties payable in the Cayman Islands, the
United Kingdom or the United States in connection with (A) the issuance of
Ordinary Shares upon any Conversion and Exchange and (B) their deposit with the
ADR Depositary against issuance of American depositary receipts (the "ADRs")
evidencing American depositary shares representing the Ordinary Shares,
provided, however, that the Guarantor shall not be required to pay any tax or
duty which may be payable in respect of any transfer involved in the issue and
delivery of Preference Shares, Ordinary Shares or ADSs in a name other than that
of the Holder of the Security or Securities to be converted, and no such issue
or delivery shall be made unless and until the Person requesting such issue has
paid to the Issuer or the Guarantor the amount of any such tax or duty, or has
established to the satisfaction of the Issuer and the Guarantor that such tax or
duty has been paid. The Guarantor will not be obligated to pay, and each
relevant Holder of Preference Shares must pay, all other taxes arising in
connection with such exchange.

     (e) The Guarantor agrees that it will, at all times while Securities are
outstanding, save with either (i) the written consent of the Holders of not less
than a majority in principal amount of the Outstanding Securities, by Act of
said Holders delivered to the Issuer, the Company and the Trustee; (ii) the
adoption of a resolution, at a meeting of Holders of the Outstanding Securities
at which a quorum is present, by the Holders of a majority in principal amount
of the Outstanding Securities represented at such meeting; or (iii) the consent
of the Trustee where, in the opinion of the Trustee, it is not materially
prejudicial to the interests of the Holders of the Securities to give such
approval:

          (A) at all times keep available for issue free from pre-emptive rights
     out of its authorized but unissued capital such number of Ordinary Shares
     as would enable the obligation of the Issuer to procure that Preference
     Shares issued upon conversion of the Securities be exchanged for Ordinary
     Shares in accordance with the Memorandum and Articles of Association of the
     Issuer to be satisfied in full;

          (B) not in any way modify the rights attaching to the Ordinary Shares
     with respect to voting, dividends or liquidation nor issue any other class
     of equity share capital carrying any rights which are more favorable than
     such rights except that this nothing in this clause (B) shall prevent (1)
     the issue of equity share capital to employees (including directors and
     executive officers) of the Company or any of its Subsidiaries or associated


                                       16
<PAGE>

     undertakings pursuant to any employees' share plan or option plan; (2) any
     consolidation or subdivision of the Ordinary Shares; (3) any modification
     of such rights which is not materially prejudicial to the interests of the
     Holders of the Securities; (4) any alteration to the Articles made in
     connection with any matters referred to in this clause (B) or supplemental
     or incidental thereto; (5) any issue of Ordinary Shares in connection with
     and upon (x) exchange of the exchangeable shares of Shire Acquisition Inc.
     or the remaining outstanding shares of Roberts Pharmaceutical Corporation
     or (y) the conversion of the unsecured convertible zero coupon loan note
     due to Arenol Corporation; or (6) any issue of equity share capital where
     the issue of such equity share capital results (or would, but for the fact
     that the adjustment would be less than one percent of the Exchange Ratio or
     that the relevant issue were at less than 95% of the current market price
     per Ordinary Share on the relevant Trading Day, result) in an adjustment to
     the Exchange Ratio; and

          (C) not reduce its issued share capital, share premium account or
     capital redemption reserve or any uncalled liability in respect thereof
     except (1) pursuant to the terms of issue of the relevant share capital;
     (2) by means of a purchase or redemption; (3) as permitted by Section
     130(2) of the Companies Act 1985; (4) where the reduction does not involve
     any distribution of assets; (5) where the reduction results in (or would,
     but for the fact that the adjustment would be less than one percent of the
     Exchange Ratio then in effect, result in) an adjustment to the Exchange
     Ratio; or (6) solely in relation to a change in the currency in which the
     nominal value of the Ordinary Shares is expressed.


                                    ARTICLE 8
                                   TERMINATION

     SECTION 8.01. Termination. This Guarantee shall terminate upon, and be of
no further force and effect from the earlier of (i) full payment of the
Redemption Price (in accordance with the Articles) for all Preference Shares
issued or issuable upon conversion of any outstanding Securities not previously
converted, or purchase and cancellation of all such Preference Shares, (ii) if
any such Preference Shares are no longer outstanding but clause (i) is not
satisfied, the full payment of the Redemption Price for all such Preference
Shares or purchase and cancellation of all such Preference Shares, (iii) full
payment of the $1,000 liquidation preference per security for all such
Preference Shares, plus any accrued and unpaid Dividends thereon, or (iv) if any
such Preference Shares are no longer outstanding but clause (i) is not
satisfied, full payment of the $1,000 liquidation preference per security for
all such Preference Shares, plus any accumulated and unpaid Dividends thereon,
provided, however, that this Guarantee will continue to be effective (x) for so
long as any Securities remain outstanding and (y) until such times as all
Holders of any Preference Shares issued or issuable upon conversion of any
outstanding Securities not previously converted have received Ordinary Shares or
ADSs or, at the Company's option, cash in exchange for such Preference Shares in
accordance with the Articles and provided further that this Guarantee will
continue to be effective or will be reinstated, as the case may be, if at any
time payment of any sums paid under the Preference Shares or this Guarantee must
be restored by a Holder thereof for any reason whatsoever.




                                       17
<PAGE>

                                    ARTICLE 9
                                 INDEMNIFICATION

     SECTION 9.01. Exculpation. (a) No Indemnified Person shall be liable,
responsible or accountable in damages or otherwise to the Guarantor or any
Covered Person for any loss, liability, expense, damage or claim incurred by
reason of any act or omission performed or omitted by such Indemnified Person in
good faith in accordance with this Guarantee and in a manner that such
Indemnified Person reasonably believed to be within the scope of the authority
conferred on such Indemnified Person by this Guarantee or by law, except that an
Indemnified Person shall be liable for any such loss, liability, expense, damage
or claim incurred by reason of such Indemnified Person's negligence or wilful
misconduct with respect to such acts or omissions.

     (b) An Indemnified Person shall be fully protected in relying in good faith
upon the records of the Guarantor and upon such information, opinions, reports
or statements presented to the Guarantor by any Person as to matters the
Indemnified Person reasonably believes are within such other Person's
professional or expert competence and who has been selected with reasonable care
by or on behalf of the Guarantor, including information, opinions, reports or
statements as to the value and amount of the assets, liabilities, profits,
losses, or any other facts pertinent to the existence and amount of assets from
which Dividends to Holders of Preference Shares might properly be paid.

     SECTION 9.02. Indemnification. The Guarantor agrees to indemnify each
Indemnified Person for, and to hold each Indemnified Person harmless against,
any and all loss, liability, damage, claim or expense incurred without
negligence or bad faith on its part, arising out of or in connection with the
acceptance or administration of the trust or trusts hereunder, including the
costs and expenses (including reasonable legal fees and expenses) of defending
itself against, or investigating, any claim or liability in connection with the
exercise or performance of any of its powers or duties hereunder. The obligation
to indemnify as set forth in this Section 9.02 shall survive the termination of
this Guarantee or the earlier resignation or removal of the Guarantee Trustee.


                                   ARTICLE 10
                                  MISCELLANEOUS

     SECTION 10.01. Successors and Assigns. All guarantees and agreements
contained in this Guarantee shall bind the successors, assigns, receivers,
trustees and representatives of the Guarantor and shall inure to the benefit of
the Holders of the Preference Shares then outstanding.

     SECTION 10.02. Amendments. Except for those changes provided for in the two
penultimate sentences of this paragraph, this Guarantee may be modified by the
Guarantor and the Guarantee Trustee only with the prior approval of the Holders
of not less than a majority in liquidation preference of the Preference Shares
in issue at the relevant time (excluding any Preference Shares beneficially
owned at that time by the Guarantor or any of its Affiliates) other than
Preference Shares purchased or acquired by the Guarantor or its Affiliates in
connection



                                       18
<PAGE>

with transactions effected by or for the account of customers of the Guarantor
or any of its Affiliates in connection with the distribution or trading of or
market-making in connection with such securities and except that persons (other
than Affiliates of the Guarantor) to whom the Guarantor or any of its
subsidiaries have pledged Preference Shares may vote or convert with respect to
such pledged securities pursuant to the terms of such pledge). This Guarantee
may be amended without the consent of the Holders of the Preference Shares to
(i) cure any ambiguity, (ii) correct or supplement any provision in this
Guarantee that may be defective or inconsistent with any other provision of this
Guarantee, (iii) add to the covenants, restrictions or obligations of the
Guarantor, (iv) conform to any change in the Investment Company Act or the rules
or regulations thereunder and (v) modify, eliminate and add to any provision of
this Guarantee to such extent as may be necessary or desirable; provided that no
such amendment shall have a material adverse effect on the rights, preferences
or privileges of the Holders of the Preference Shares. Neither Section 5.01 nor
Section 7.02 nor Section 10.02 may be amended without the prior approval of each
Holder of the Preference Shares. Any amendment hereof in accordance with this
Section 10.02 shall be binding on all Holders.

     SECTION 10.03. Judgment Currency Indemnity. (a) If, for the purposes of
obtaining judgment in any court, it is necessary to convert an amount due from
the Guarantor under any provision of this Guarantee to a currency other than the
U.S. dollar, the parties agree, to the fullest extent that they may effectively
do so, that the rate of exchange used shall be that at which, in accordance with
normal banking procedures, The Bank of New York could purchase such other
currency with U.S. dollars at its New York office on the second Business Day
preceding the day on which final judgment is given.

     (b) The obligations of the Guarantor in respect of any amount due to the
Guarantee Trustee or any Holders under this Agreement shall, notwithstanding any
judgment in a currency other than the U.S dollar, be discharged only to the
extent that on the Business Day following receipt by the Guarantee Trustee or
such Holders, as the case may be, of any amount adjudged to be so due in such
other currency, the Guarantee Trustee or such Holders, as the case may be, may
in accordance with normal banking procedures purchase U.S. dollars with such
other currency.

     (c) If the amount of U.S. dollars so purchased is less than the amount
originally due to the Guarantee Trustee or such Holders, as the case may be, in
U.S. dollars, the Guarantor agrees, to the fullest extent that it may
effectively do so, as a separate obligation and notwithstanding any such
judgment, to indemnify the Guarantee Trustee or such Holders, as the case may
be, against such loss.

     (d) If the amount of U.S. dollars so purchased exceeds the amount
originally due to the Guarantee Trustee or such Holders, as the case may be, the
Guarantee Trustee or such Holders, as the case may be, agree to remit any
remaining amount to the Guarantor in pounds sterling.

     SECTION 10.04. Assignment of the Guarantor. The Guarantor will not assign
its obligations under the Guarantee, except in the case of a merger,
consolidation or a sale or contribution of substantially all of its assets,
where the Guarantor is not the surviving entity.



                                       19
<PAGE>

     SECTION 10.05. Notices. All notices provided for in this Guarantee shall be
in writing, duly signed by the party giving such notice, and shall be delivered,
telecopied or mailed by first class mail, as follows:

          (a) If given to the Guarantee Trustee, at the Guarantee Trustee's
     mailing address set forth below:

              The Bank of New York
              101 Barclay Street
              Floor 2l West
              New York, NY 10286

              Attention: Corporate Trust Administration-- Sunjeeve Patel
              Facsimile: 212-815-5915

          (b) If given to the Guarantor, at the Guarantor's mailing address set
     forth below (or such other address as the Guarantor may give notice of to
     the Holders of the Preference Shares):

              Hampshire International Business Park
              Chineham, Basingstoke
              Hampshire  RG24 8EP
              England

              Attention:  Company Secretary

          (c) If given to any Holder of Preference Shares, at the address set
     forth in the Register.

     All such notices shall be deemed to have been given when received in
person, telecopied with receipt confirmed, or mailed by first class mail,
postage prepaid except that if a notice or other document is refused delivery or
cannot be delivered because of a changed address of which no notice was given,
such notice or other document shall be deemed to have been delivered on the date
of such refusal or inability to deliver.

     SECTION 10.06. Governing Law. THIS GUARANTEE SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK,
WITHOUT REGARD TO CONFLICTS OF LAWS PRINCIPLES THEREOF, EXCEPT FOR SECTION 6.01
HEREOF, WHICH SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE
WITH, THE LAWS OF ENGLAND AND WALES, WITHOUT REGARD TO CONFLICTS OF LAWS
PRINCIPLES THEREOF. THE PARTIES HERETO EACH HEREBY WAIVE ANY RIGHT TO TRIAL BY
JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM ARISING OUT OF OR RELATING TO
THIS AGREEMENT OR ANY TRANSACTION RELATED HERETO.



                                       20
<PAGE>

     SECTION 10.07. Jurisdiction and Service of Process. (a) Any claim or
proceeding brought by the Guarantee Trustee on behalf of Holders or a Holder to
enforce the obligations of the Guarantor hereunder, including, without
limitation, any claims, counter-claims and cross-claims asserted against the
Guarantee Trustee in connection therewith, shall be brought in a court of
competent jurisdiction in England and Wales or the State of New York.

     (b) The Guarantor irrevocably consents to the jurisdiction of any court of
the State of New York or any United States federal court sitting in the Borough
of Manhattan, New York City, New York, United States, and any appellate court
from any thereof, and waives any immunity from the jurisdiction of such courts
over any suit, action or proceeding that may be brought in connection with this
Guarantee. The Guarantor irrevocably waives, to the fullest extent permitted by
law, any objection to any suit, action, or proceeding that may be brought in
connection with this Guarantee in such courts whether on the grounds of venue,
residence or domicile or on the ground that any such suit, action or proceeding
has been brought in an inconvenient forum. The Guarantor agrees that final
judgment in any such suit, action or proceeding brought in such court shall be
conclusive and binding upon the Guarantor and may be enforced in any court to
the jurisdiction of which the Guarantor is subject by a suit upon such judgment;
provided that service of process is effected upon the Guarantor in the manner
provided herein. Notwithstanding the foregoing, any suit, action or proceeding
brought in connection with this Guarantee may be instituted in any competent
court in England and Wales.

     (c) The Guarantor agrees that service of all writs, process and summonses
in any suit, action or proceeding brought in connection with this Guarantee
against the Guarantor in any court of the State of New York or any United States
federal court sitting in the Borough of Manhattan, New York City may be made
upon CT Corporation System at 111 8th Avenue, 13th Floor, New York, New York
10011, whom the Guarantor irrevocably appoints as its authorized agent for
service of process. The Guarantor represents and warrants that CT Corporation
System has agreed to act as the agent for service of process for the Guarantor.
The Guarantor agrees that such appointment shall be irrevocable so long as any
of the Securities or Preference Shares remain outstanding or until the
irrevocable appointment by the Guarantor of a successor in The City of New York
as its authorized agent for such purpose and the acceptance of such appointment
by such successor. The Guarantor further agrees to take any and all action,
including the filing of any and all documents and instruments, that may be
necessary to continue such appointment in full force and effect as aforesaid. If
CT Corporation System shall cease to act as the agent for service of process for
the Guarantor, the Guarantor shall appoint without delay another such agent and
provide prompt written notice to the Guarantee Trustee of such appointment. With
respect to any such action in any court of the State of New York or any United
States federal court in the Borough of Manhattan, New York City, service of
process upon CT Corporation System, as the authorized agent of the Guarantor for
service of process, and written notice of such service to the Guarantor shall be
deemed, in every respect, effective service of process upon the Guarantor.

     (d) Nothing in this Section shall affect the right of any party to serve
legal process in any other manner permitted by law.




                                       21
<PAGE>


     THIS GUARANTEE is executed as of the day and year first above written.


                                        SHIRE PHARMACEUTICALS
                                        GROUP PLC,
                                          as Guarantor



                                        By:
                                           ------------------------------------
                                             Name:
                                             Title:




THE BANK OF NEW YORK,
  as Guarantee Trustee



By:
   -----------------------------------------
     Name:
     Title: