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                                                                   EXHIBIT 10.52

                                AMENDMENT 1999-1

                              BECKMAN COULTER, INC.
                                  SAVINGS PLAN


         WHEREAS, Beckman Coulter, Inc. (the "Company"), a Delaware corporation
maintains the Beckman Coulter, Inc. Savings Plan (the "Plan"); and

         WHEREAS, the Company now desires to amend the Plan to clarify certain
provisions; and

         WHEREAS, the Company has the right to amend the Plan;

         NOW, THEREFORE, the Plan is hereby amended as follows, effective as of
the date of adoption of this Amendment 1999-1, except as otherwise indicated
below:

         1. The definition of "Committee" in Section 1.2 of the Plan is hereby
amended to read as follows:

                  "'Committee' shall mean the Benefits Finance and
                  Administration Committee appointed by the Board pursuant to
                  Article VII."

         2. The definition of "Plan Compensation" in Section 1.2 of the Plan is
hereby amended by adding the following as a new fourth sentence; such amendment
is considered a clarification of the previous intent of the Company, and does
not constitute a substantive change:

                  "Plan Compensation shall not include amounts deferred under
                  the Company's non-qualified deferred compensation programs,
                  such as its Executive Deferred Compensation Plan and Executive
                  Restoration Plan."

         3. Effective September 1, 1998, the first sentence of Section 6.8 is
hereby amended to read as follows:

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                  "The total number of withdrawals referred to in Sections 6.1,
                  6.2, 6.3, 6.4 and 6.5 shall not exceed four in any Plan Year
                  for any Participant."

         4. The first sentence of Section 7.1 of the Plan is amended to read as
follows:

                  "The Committee is the Benefits Finance and Administration
                  Committee, which is appointed by, and serves at the pleasure
                  of, the Board."

         5. The reference to the "Committee" in Section 8.1 of the Plan is
changed to a reference to the "Corporate Benefits Committee" of the Company.

         6. Section 9.11(c)(2) shall be amended by adding the following to the
end of the section:

                  "Loan repayments may be suspended during a Participant's
                  active military service, as provided in Code Section
                  414(u)(4)."

         7. Effective September 1, 1998, Section 9.11(c)(3)(B) of the Plan shall
be deleted and Section 9.11(c)(3)(C) shall be redesignated as Section
9.11(c)(3)(B).

         8. Effective January 1, 2000, Section 1.2(c) of Appendix A shall have
no further force and effect.

         9. Effective October 21, 1996, Section 1 of Appendix C is amended by
adding the following to the end of the section:

                  "Genomyx Corporation was added as a Participating Affiliate
                  effective October 21, 1996; provided, however, that employees
                  of Genomyx Corporation were not entitled to allocations of
                  Company Matching Contributions."

         10. Effective May 1, 1998, Section 1 of Appendix C is amended by adding
the following to the end of the section:

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                  "Effective May 1, 1998, the employees of Genomyx Corporation
                  became employees of the Company, and they therefore became
                  eligible for allocations of Company Matching Contributions
                  from that time forward."

         11. Effective July 28, 1999, Section 1 of Appendix C is amended by
adding the following to the end of the section:

                  "Each individual who became a Covered Employees as a result of
                  the 'Strategic Alliance and Cross Distribution Agreement
                  between Beckman Coulter, Inc. and C.H. Werfen S.A.,' signed
                  July 28, 1999 (sometimes referred to as 'MLA and Ortho
                  employees'), shall be credited for purposes of determining
                  eligibility under this Plan with such individual's service
                  with the C.H. Werfen S.A. entity which employed such
                  individual prior to becoming a Covered Employee."

         12. Effective October 31, 1997, Section 1 of Appendix F is amended to
provide as follows:

                  "Each Covered Employee who as of October 31, 1997 was
                  classified by the Company as an employee rendering services to
                  Coulter Corporation is subject to the provisions of the
                  Appendix F (a "Coulter Employee"). With respect to individuals
                  not employed by the Company as of October 31, 1997 the
                  following rules shall apply: (1) If such Covered Employee had
                  no prior service with Beckman Instruments, Inc. or Coulter
                  Corporation, and the Covered Employee's first Hour of Service
                  is performed at a facility, location or operation determined
                  by the Company to be primarily related to the portion of the
                  Company's business acquired through the acquisition of Coulter
                  Corporation, that person shall be a "Coulter Employee" for
                  purposes of this Appendix F. (2) If such a Covered

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                  Employee's first Hour of Service is after October 31, 1997,
                  and he has prior service with either Coulter Corporation or
                  Beckman Instruments, Inc., then he shall be classified as a
                  "Coulter Employee" upon rehire if he was most recently
                  employed by Coulter Corporation (rather than Beckman
                  Instruments, Inc.) prior to October 31, 1997. Otherwise, upon
                  rehire by the Company he shall be classified as a "Beckman
                  Employee." The initial classification of an Employee as a
                  "Coulter Employee" or "Beckman Employee" shall continue
                  notwithstanding any change to the Employee's facility,
                  location or operation or any subsequent termination and
                  rehire."

         13. Effective September 1, 1998, the first sentence of subsection 6(5)
of Appendix F of the Plan is amended to provide as follows:

                  "(5) Amounts credited to a Coulter Employee's "Pension Plan
                  Account" and "Retirement Plus Account" under the Plan shall be
                  available for distribution as provided under Section 6.6 after
                  the Coulter Employee's Severance from Service, or after the
                  Coulter Employee reaches age 70-1/2, pursuant to Section
                  6.10(b)"

         14. Effective September 1, 1998, the second sentence of the first
paragraph of Section 7 of Appendix F is amended to read as follows:

                  "Commencing September 1, 1998, as of the end of each calendar
                  quarter (ending march 31, June 30, September 30, and December
                  31) in each Plan Year, the Company shall make a "Retirement
                  Plus Contribution" to the Retirement Plus Contributions
                  Account of each Coulter Employee who, as of the last working
                  day of that quarter (i) is a Covered Employee and (ii) has
                  completed a twelve month Period of Service with the Company or
                  a Related Company.

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         15. Effective September 1, 1998, the first sentence of the second
paragraph of Section 7 of Appendix F is amended to read as follows:

                  "In addition, for each Coulter Employee who was (1) hired on
                  or before November 1, 1995, (2) was employed by Coulter
                  Corporation on March 31, 1996, and (3) was a participant in
                  the Coulter Corporation Pension Plan on March 31, 1996, the
                  Company shall make the quarterly contribution shown in the
                  following table to the Retirement Plus Contributions Account
                  of each such Coulter Employee who is a Covered Employee on the
                  last working day of that quarter."

                  IN WITNESS WHEREOF, this Amendment 1999-1 is hereby adopted
this 20th day of December, 1999.

                                         BECKMAN COULTER, INC.


                                         By /s/ Fidencio M. Mares
                                            ------------------------------------
                                            Fidencio M. Mares
                                            Its Vice President - Human Resources