FORM 4

o Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

(Print or Type Responses)
  UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF
CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934,
Section 17(a) of the Public Utility Holding Company Act of 1935 or
Section 30(h) of the Investment Company Act of 1940
 
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1.   Name and Address of Reporting Person*   2.   Issuer Name and Ticker or Trading Symbol   6.   Relationship of Reporting Person(s) to Issuer
(Check all applicable)
    Reuter   Bruce           MacroPore Biosurgery, Inc.                Director            10% Owner

 
           
    (Last)   (First)   (Middle)   3.   I.R.S. Identification Number of Reporting Person, if an entity (voluntary)   4.   Statement for
Month/Day/Year
        X   Officer (give
        title below)
           Other
        (specify below)
    6740 Top Gun Street               November 13, 2002       Sr. Vice President of International Sales

 
 
     
(Street)           5.   If Amendment, Date of Original (Month/Day/Year)   7.   Individual or Joint/Group Filing
(Check Applicable Line)
    X     Form filed by One Reporting Person
             Form filed by More than One
    San Diego   CA   92121                                   Reporting Person

    (City)   (State)   (Zip)                            
Table I — Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.   Title of Security
(Instr. 3)
  2.   Transaction Date   2A.   Deemed Execution Date, if any   3.   Transaction Code
(Instr. 8)
  4.   Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
  5.   Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
  6.   Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
  7.   Nature of Indirect Beneficial Ownership
(Instr. 4)
            (Month/Day/Year)   (Month/Day/Year)  
                       
                            Code   V       Amount   (A) or (D)   Price                        

Common Stock   11/13/02(1)               A(2)           2,193   A   (2)       4,193       D        

                                                                         

                                                                         

                                                                         

                                                                         

                                                                         

                                                                         


Table II — Derivative Securities Acquired, Disposed of, or Beneficially Owned
(
e.g., puts, calls, warrants, options, convertible securities)


1.   Title of Derivative Security
(Instr. 3)
  2.   Conversion or Exercise Price of Derivative Security   3.   Transaction Date
(Month/Day/Year)
  3A.   Deemed Execution Date, if any
(Month/Day/Year)
  4.   Transaction Code
(Instr. 8)
  5.   Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
  6.   Date Exercisable and Expiration Date (Month/Day/Year)
                               
 
                                    Code   V       (A)   (D)       Date
Exercisable
  Expiration Date

                                                                 

                                                                 

                                                                 

                                                                 

                                                                 

                                                                 

                                                                 

                                                                 

                                                                 

                                                                 

                                                                 


7.   Title and Amount of Underlying Securities
(Instr. 3 and 4)
  8.   Price of Derivative Security
(Instr. 5)
  9.   Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
  10.   Ownership Form of Derivative Securities: Direct (D) or Indirect (I) (Instr. 4)   11.   Nature of Indirect Beneficial Ownership
(Instr. 4)
   
                               
    Title   Amount or Number of Shares                                

                                         

                                         

                                         

                                         

                                         

                                         

                                         

                                         

                                         

                                         

                                         

Explanation of Responses:

(1)    The transaction date was fixed at the effective closing of the Merger between StemSource Inc. and MacroPore Biosurgery, Inc.

(2)    Mr. Reuter acquired the shares by virture of the merger exchange of 10,000 common shares of StemSource Inc. in return for 2,193 shares of MacroPore Biosurgery, Inc. The MacroPore shares were valued at $4.15 each on the date of closing.

/s/ Bruce Reuter   01/30/03

**Signature of Reporting Person
 
Date

Reminder:

 

Report on a separate line for each class of securities beneficially owned directly or indirectly.

*

 

If the form is filed by more than one reporting person,
see Instruction 4(b)(v).

**

 

Intentional misstatements or omissions of facts constitute Federal Criminal Violations.
See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note:

 

File three copies of this Form, one of which must be manually signed. If space is insufficient,
see Instruction 6 for procedure.