Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

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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(Print or Type Responses)
1. Name and Address of Reporting Person *
FINGER JENNIFER J
   2. Issuer Name and Ticker or Trading Symbol
WESTAMERICA BANCORPORATION [WABC] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP/Treasurer
(Last)
(First)
(Middle)
WESTAMERICA BANCORPORATION, 4550 MANGELS BLVD.		 3. Date of Earliest Transaction (Month/Day/Year)
10/21/2011
(Street)

FAIRFIELD, CA 94534		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One 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 (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 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)
Code V Amount (A) or (D) Price
Common Stock 10/21/2011   M   15,848 A $ 38.74 21,750.809 D  
Common Stock 10/21/2011   S   15,848 D $ 43.0918 (1) 5,902.809 D  
Common Stock 10/21/2011   M   992 A $ 38.74 6,894.809 D  
Common Stock               25,030 I Deferred
Common Stock               1,287.56 (2) I Esop

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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)		 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 Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Non-qualified Stock Option (Right to Buy) $ 38.74 10/21/2011   M     15,848 01/23/2003 01/23/2012 Common Stock 15,848 $ 0 992 D  
Non-qualified Stock Option (Right to Buy) $ 38.74 10/21/2011   M     992 01/23/2003 01/23/2012 Common Stock 992 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
FINGER JENNIFER J
WESTAMERICA BANCORPORATION
4550 MANGELS BLVD.
FAIRFIELD, CA 94534		       SVP/Treasurer  

Signatures

 /s/ Jennifer J. Finger   10/24/2011
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) This is a weighted average price of multiple transactions for the same option. The sale price ranges from $43.00 to $43.29.
(2) Incudes allocations through 9/30/2011 in Westamerica Bancorporation's Tax Deferred Savings/Retirement (ESOP) Plan.

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