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 *
KROPP JAMES H
   2. Issuer Name and Ticker or Trading Symbol
PS BUSINESS PARKS INC/CA [PSB] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
C/O PS BUSINESS PARKS, INC., 701 WESTERN AVENUE		 3. Date of Earliest Transaction (Month/Day/Year)
05/15/2012
(Street)

GLENDALE, CA 91201-2397		 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               4,491 I by IRA (1)
Common Stock 05/15/2012   M   2,000 A $ 32.48 8,434 D  
Common Stock 05/15/2012   S   1,500 D $ 68.2243 (4) 6,934 D  
Depositary Shares Representing Series P Preferred Stock               1,117 I by IRA (1)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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
Stock Option (right to buy) (3) $ 68.25             04/30/2013 04/30/2022 Common Stock 2,000   2,000 D  
Stock Option (right to buy) (2) $ 60.66             05/02/2012 05/02/2021 Common Stock 2,000   2,000 D  
Stock Option (right to buy) (2) $ 60.82             05/03/2011 05/03/2020 Common Stock 2,000   2,000 D  
Stock Option (right to buy) (2) $ 43.84             05/04/2010 05/04/2019 Common Stock 2,000   2,000 D  
Stock Option (right to buy) (2) $ 57.79             05/05/2009 05/05/2018 Common Stock 2,000   2,000 D  
Stock Option (right to buy) (2) $ 68.9             04/30/2008 04/30/2017 Common Stock 2,000   2,000 D  
Stock Option (right to buy) (2) $ 51.25             05/01/2007 05/01/2016 Common Stock 2,000   2,000 D  
Stock Option (right to buy) (2) $ 39.95             05/03/2006 05/03/2015 Common Stock 2,000   2,000 D  
Stock Option (right to buy) (2) $ 39.26             05/04/2005 05/04/2014 Common Stock 2,000   2,000 D  
Stock Option (right to buy) (2) $ 32.48 05/15/2012   M     2,000 05/06/2004 05/06/2013 Common Stock 2,000 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
KROPP JAMES H
C/O PS BUSINESS PARKS, INC.
701 WESTERN AVENUE
GLENDALE, CA 91201-2397		   X      

Signatures

 /s/ Stephanie G. Heim, Attorney in Fact   05/17/2012
**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) By a custodian of an IRA for benefit of the reporting person.
(2) Stock Options granted pursuant to the 2003 Stock Option and Incentive Plan; options vest in 5 equal annual installments beginning 1 year from date of grant.
(3) Stock Options granted pursuant to the 2012 Equity and Performance-Based Compensation Plan; options vest in 5 equal annual installments beginning 1 year from date of grant.
(4) Represents weighted average purchase price. These shares were sold at price ranging between $68.0400 and $68.5200. Full information regarding the number of shares purchased at each separate purchase price will be provided by the reporting person upon request to the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer.

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