AMENDMENT NO. 1 TO

                            SERVICE AGREEMENT BETWEEN

                        HUNTINGDON LIFE SCIENCES LIMITED

                                       AND

                                   BRIAN CASS





                           DATED AS OF APRIL 15, 2002





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     This is Amendment No. 1, dated as of April 15, 2002 (this  "Amendment")  to
that certain Service  Agreement,  dated as of April 29, 1999 (the  "Agreement"),
between  Huntingdon  Life Sciences  Limited (the  "Company") and Brian Cass (the
"Executive").  Capitalized  terms  used but not  defined  herein  shall have the
meanings ascribed to them in the Agreement.

     In  consideration of the promises and mutual covenants set forth herein and
in the Agreement, the parties hereto agree as follows:

     1.   The  definition of the term  "Holding  Company" in Section 1(1) of the
          Agreement  shall be  amended  to  delete  the words  "Huntingdon  Life
          Sciences  Group plc" and replace  them with "Life  Sciences  Research,
          Inc."

     2.   The duties of Executive in Section  3(1)(a) of the Agreement  shall be
          amended  to add after the words  "Managing  Director"  the words  "and
          President of Holding Company".

     3.   The  remuneration  of the  Executive  set forth in Section 7(1) of the
          Agreement  shall be  amended  by  deleting  the words  "(pound)150,000
          gross" and replacing them with the words "(pound)200,000 gross".

     4.   The provision with respect to payment to Executive upon termination of
          employment  set  forth  in  Section  18(1) of the  Agreement  shall be
          amended by adding after the last word of the sole sentence thereof the
          words " in an amount equal to the Executive's  annualized  salary plus
          any additional  compensation (such as bonus or incentive compensation)
          earned or  received  by the  Executive  from the  Company in the prior
          twelve months."

     5.   Section 22 of the  Agreement  with  respect to payment to Executive in
          connection  with  termination  of  employment  following  a Change  of
          Control  is hereby  deleted  in its  entirety  and  replaced  with the
          following:

     If within the  twelve  months  following  a Change of Control of Parent the
Executive's  employment  is  terminated  by the  Company  without  Cause  or the
Executive  resigns such  employment  for Good Reason,  then within 30 days after
such  termination  or  resignation  the Company  shall make a lump sum severance
payment in cash to Executive  in an amount  equal to 2.99 times the  Executive's
then current annualized base salary plus 2.99 times any additional  compensation
(such as bonus or incentive  compensation)  earned during the 12 months prior to
such termination or resignation.

     For purposes of this Section 14(3),  and  notwithstanding  any other use of
the specified term elsewhere in this Agreement,

          "Cause"  shall mean (a) breach of fiduciary  duty  involving  personal
     profit,  (b) conviction of a felony,  (c) violation of the  confidentiality
     provisions of this Agreement or (d)  intentional  failure to perform stated
     duties  of  employment  that  materially  adversely  affect  the  Company's
     interests.

          "Change of Control" shall mean,  notwithstanding  the prior occurrence
     of any other event  constituting a "change of control" (a) the  acquisition
     by any person or group of, or the  entering  into of any  agreement  by any
     person or group to acquire by purchase, merger, consolidation or otherwise,
     or the  commencement  of a tender offer or exchange  offer by any person or
     group  for,  beneficial   ownership  (within  the  meaning  of  Rule  13d-3
     promulgated  under the  Securities  Exchange  Act of 1934,  as  amended) of
     shares  resulting in the  beneficial  ownership of thirty  percent (30%) or
     more of the total  number of votes  which may be cast for the  election  of
     directors of Parent,  or (b) the  acquisition by any person or group or the
     entering  into of any  agreement  by any person or group to acquire  all or
     substantially  all of the assets of the Parent, or (c) the persons who were
     directors of the Parent  prior to any cash tender offer or exchange  offer,
     merger or other business combination or other  reorganization,  sale of all
     or substantially all of Parent's assets, contested or other election or any
     combination  of the foregoing  transactions  cease to constitute at least a
     majority of the Board following any of such transactions,  or (d) any other
     change  of  control  of a nature  that  would be  required  to be  reported
     (assuming such event has not been previously  reported) in response to Item
     1(a) of the Current  Report on Form 8-K,  as in effect on the date  hereof,
     pursuant to Section 13 or 15(d) of the Securities  Exchange Act of 1934, as
     amended."

     "Good Reason" shall mean:

          (a) After a Change of Control of the Parent shall have  occurred,  and
     without the express  written  consent of Executive,  he is given a title or
     assigned any duties  materially  inconsistent  with his  position,  duties,
     responsibilities  or status with the Company as in effect immediately prior
     to such Change of Control;

          (b) The  base  salary  of  Executive,  and/or  incentive  compensation
     opportunity  and/or  benefits,  is reduced below that in effect at the date
     hereof or at the time of the Change of Control as applicable; or

          (c) Without the express written  consent of Executive,  he is required
     after a Change of  Control  to be  permanently  based  anywhere  other than
     within a 30 mile radius of his office location  immediately prior to Change
     of Control,  except for  required  travel on the  Company's  business to an
     extent consistent with his duties hereunder.

     5. This Amendment shall be binding upon any successors or permitted assigns
of the Company and/or Parent.

     6. This Amendment shall be governed by the laws of England.

     The parties  hereto have  executed and delivered  this  Amendment as of the
date first above written.

HUNTINGDON LIFE SCIENCES LIMITED

By:      /s/ Julian Griffiths
Name:     Julian Griffiths
Title:    Company Secretary

BRIAN CASS

/s/ Brian Cass
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