U.S. SECURITIES AND EXCHANGE COMMISSION Washington, DC 20549 FORM 4 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(f) of the Investment Company Act of 1940 [_] Check box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b). ------------------------------------------------------------------------------- 1. Name and Address of Reporting Person* VA Partners, LLC ------------------------------------------------------------------------------- (Last) (First) (Middle) One Maritime Plaza, Suite 1400 ------------------------------------------------------------------------------- (Street) San Francisco CA 94111 ------------------------------------------------------------------------------- (City) (State) (Zip) ------------------------------------------------------------------------------- 2. Issuer Name and Ticker or Trading Symbol Mentor Corporation (MNTR) ------------------------------------------------------------------------------- 3. IRS Identification Number of Reporting Person, if an Entity (Voluntary) ------------------------------------------------------------------------------- 4. Statement for Month/Day/Year APRIL 16, 2003 ------------------------------------------------------------------------------- 5. If Amendment, Date of Original (Month/Day/Year) ------------------------------------------------------------------------------- 6. Relationship of Reporting Person to Issuer (Check all applicable) [ ] Director [X] 10% Owner [_] Officer (give title below) [_] Other (specify below) ------------------------------------------------------------------------------- 7. Individual or Joint/Group Filing (Check applicable line) [ ] Form filed by one Reporting Person [X] Form filed by more than one Reporting Person ------------------------------------------------------------------------------- =============================================================================== Table I -- Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned ===================================================================== 6. 4. 5. Owner- Securities Acquired (A) Amount of ship 3. or Disposed of (D) Securities Form: 7. Transaction (Instr. 3, 4 and 5) Beneficially Direct Nature of 2. 2A. Deemed Code ------------------------ Owned Following (D) or Indirect 1. Transaction Execution (Instr. 8) (A) Reported Transaction Indirect Beneficial Title of Security Date Date, if any ------------ Amount or Price (Instr. 3 (I) Ownership (Instr. 3) (mm/dd/yy) (mm/dd/yy) Code V (D) and 4) (Instr.4) (Instr. 4) -------------------------------------------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------------------------------------- Common Stock 04/16/03 P 13,000 A 17.00 5,909,018(1)(2) I (1)(2) -------------------------------------------------------------------------------------------------------------------------------- ================================================================================================================================ 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). Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. (Over) SEC 1474 (3-00) PAGE 2 OF 5 FORM 4 (continued) Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities) ============================================================================== 10. 9. Owner- Number ship of Form 2. Deriv- of Conver- 5. 7. ative Deriv- 11. sion Number of Title and Amount Secur- ative Nature or Derivative 6. of Underlying 8. ities Secur- of Exer- 4. Securities Date Securities Price Bene- ity: In- cise 3. Trans- Acquired (A) Exercisable and (Instr. 3 and 4) of ficially Direct direct Price Trans- action or Disposed Expiration Date ---------------- Deriv- Owned (D) or Bene- 1. of action Code of(D) (Month/Day/Year) Amount ative Following In- ficial Title of Deriv- Date (Instr. (Instr. 3, ---------------- or Secur- Reported direct Owner- Derivative ative (Month/ 8) 4 and 5) Date Expira- Number ity Transaction (I) ship Security Secur- Day/ ------ ------------ Exer- tion of (Instr. (Instr. (Instr. (Instr. (Instr. 3) ity Year) Code V (A) (D) cisable Date Title Shares 5) 4) 4) 4) ----------------------------------------------------------------------------------------------------------------------------------- ----------------------------------------------------------------------------------------------------------------------------------- ----------------------------------------------------------------------------------------------------------------------------------- Explanation of Responses: (1)As General Partner and Investment Manager of ValueAct Capital Partners, L.P., ValueAct Capital Partners II, L.P., and ValueAct Capital International, Ltd. (2)These securities are also beneficially owned by Jeffrey W. Ubben, George F. Hamel, Jr., and Peter H. Kamin as Managing Members, Principal Owners and Controlling Persons of VA Partners, LLC. VALUEACT CAPITAL PARTNERS, L.P., BY VA PARTNERS, L.L.C., ITS GENERAL PARTNER By: /s/ George F. Hamel, Jr. 04/17/03 ----------------------------------------- ---------------- George F. Hamel, Jr. Date Managing Member **Signature of Reporting Person VALUEACT CAPITAL PARTNERS II, L.P., BY VA PARTNERS, L.L.C., ITS GENERAL PARTNER By: /s/ George F. Hamel, Jr. 04/17/03 ----------------------------------------- ---------------- George F. Hamel, Jr. Date Managing Member **Signature of Reporting Person VALUEACT CAPITAL INTERNATIONAL, LTD., BY VA PARTNERS, L.L.C., ITS INVESTMENT MANAGER By: /s/ George F. Hamel, Jr. 04/17/03 ----------------------------------------- ---------------- George F. Hamel, Jr. Date Managing Member **Signature of Reporting Person PAGE 3 OF 5 VA PARTNERS, L.L.C. By: /s/ George F. Hamel, Jr. 04/17/03 ------------------------------------------ ---------------- George F. Hamel, Jr. Date Managing Member **Signature of Reporting Person By: /s/ Jeffrey W. Ubben 04/17/03 ----------------------------------------- ---------------- Jeffrey W. Ubben Date **Signature of Reporting Person By: /s/ George F. Hamel, Jr. 04/17/03 ------------------------------------------ ---------------- George F. Hamel, Jr. Date **Signature of Reporting Person By: /s/ Peter H. Kamin 04/17/03 --------------------------------------------- ----------------- Peter H. Kamin Date **Signature of Reporting Person ** 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 provided is insufficient, see Instruction 6 for procedure. PAGE 4 OF 5 Joint Filer Information Name: ValueAct Capital Partners, L.P. Address: One Maritime Plaza, Suite 1400, San Francisco, CA 94111 Designated Filer: VA Partners, L.L.C. Issuer and Ticker Symbol: Mentor Corporation (MNTR) Date of Event Requiring Statement: April 16, 2003 Name: ValueAct Capital Partners II, L.P. Address: One Maritime Plaza, Suite 1400, San Francisco, CA 94111 Designated Filer: VA Partners, L.L.C. Issuer and Ticker Symbol: Mentor Corporation (MNTR) Date of Event Requiring Statement: April 16, 2003 Name: ValueAct Capital International, Ltd. Address: One Maritime Plaza, Suite 1400, San Francisco, CA 94111 Designated Filer: VA Partners, L.L.C. Issuer and Ticker Symbol: Mentor Corporation (MNTR) Date of Event Requiring Statement: April 16, 2003 Name: Jeffrey W. Ubben Address: One Maritime Plaza, Suite 1400, San Francisco, CA 94111 Designated Filer: VA Partners, L.L.C. Issuer and Ticker Symbol: Mentor Corporation (MNTR) Date of Event Requiring Statement: April 16, 2003 Name: George F. Hamel, Jr. Address: One Maritime Plaza, Suite 1400, San Francisco, CA 94111 Designated Filer: VA Partners, L.L.C. Issuer and Ticker Symbol: Mentor Corporation (MNTR) Date of Event Requiring Statement: April 16, 2003 Name: Peter H. Kamin Address: One Maritime Plaza, Suite 1400, San Francisco, CA 94111 Designated Filer: VA Partners, L.L.C. Issuer and Ticker Symbol: Mentor Corporation (MNTR) Date of Event Requiring Statement: April 16, 2003 PAGE 5 OF 5