1. Name and Address of Reporting Person THIER, SAMUEL O. 251 Ballardvale Street Wilmington, MA 01887 USA 2. Issuer Name and Ticker or Trading Symbol Charles River Laboratories Int'l., Inc (CRL) 3. IRS or Social Security Number of Reporting Person (Voluntary) 4. Statement for Month/Year 5/2002 5. If Amendment, Date of Original (Month/Day/Year) 6. Relationship of Reporting Person(s) to Issuer (Check all applicable) (X) Director ( ) 10% Owner ( ) Officer (give title below) ( ) Other (specify below) 7. Individual or Joint/Group Filing (Check Applicable Line) (X) Form filed by One Reporting Person ( ) Form filed by More than One Reporting Person TABLE I -- Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned +---------------------------------+----------+-------------+-----------------------------+----------------+-----------+------------+ |1. Title of Security |2. Trans- |3. Trans- |4. Securities Acquired (A) |5. Amount of |6. Owner- |7. Nature | | | action | action | or Disposed of (D) | Securities | ship | of In- | | | Date | Code | | Beneficially | Form: | direct | | | | | | Owned at | Direct | Bene- | | | (Month/ | | | End of | (D) or | ficial | | | Day/ +-------+-----+-----------+------+----------+ Month | Indirect| Owner- | | | Year) |Code |V |Amount |A/D |Price | | (I) | ship | +---------------------------------+----------+-------+-----+-----------+------+----------+----------------+-----------+------------+ TABLE II -- Derivative Securities Acquired, Disposed of, or Beneficially Owned +-------------+--------+----------+---------+-----------+---------------------+----------------+----------+--------+-------+-------+ |1. |2. |3. |4. |5. |6. |7. |8. |9. |10. |11. | | | | | | | | | |Number |Owner- | | | | | | | | | | |of |ship | | | | | | | | | | |Deriv- |Form of| | | | | | | | |Title and Amount| |ative |Deriv- | | | | | | | | |of Underlying | |Secur- |ative |Nature | | |Conver- | | |Number of | |Securities | |ities |Secur- |of | | |sion or | | |Derivative |Date Exercisable +-------+--------+ |Benefi- |ity: |In- | | |Exercise| | |Securities |and Expiration Date | |Amount | |cially |Direct |direct | | |Price of|Transac- |Transac- |Acquired(A)|(Month/Day/Year) | |or | |Owned |(D) or |Bene- | |Title of |Deriv- |tion Date |tion Code|Disposed(D)+----------+----------+ |Number |Price of |at End |In- |ficial | |Derivative |ative |(Month/ +------+--+-----+-----+Date Exer-|Expira- | |of |Derivative|of |direct |Owner- | |Security |Security|Day/Year) |Code |V |(A) |(D) |cisable |tion Date |Title |Shares |Security |Month |(I) |ship | +-------------+--------+----------+------+--+-----+-----+----------+----------+-------+--------+----------+--------+-------+-------+ Stock Options $33.7 05/03/2002 A V 6000 05/03/2004 05/03/2007 Common 6000 $0.0000 6000 D (Right to buy) Stock Explanation of Responses: SIGNATURE OF REPORTING PERSON /s/ SAMUEL O. THIER DATE 06/04/2002