X0306 4 2012-12-14 0 0000866368 PS BUSINESS PARKS INC/CA PSB 0001227459 HAWTHORNE MARIA R C/O PS BUSINESS PARKS, INC 701 WESTERN AVENUE GLENDALE CA 91201-2397 0 1 0 0 SENIOR VICE PRESIDENT Common Stock 2012-12-14 4 M 0 4000 52.35 A 18505 D Common Stock 2012-12-14 4 S 0 4000 63.6554 D 14505 D Common Stock 2012-12-14 4 S 0 3500 63.6498 D 11005 D Common Stock 8886.2223 I By 401(k) Plan Stock Option (right to buy) 52.35 2012-12-14 4 M 0 4000 0 D 2011-03-15 2020-03-15 Common Stock 4000 24000 D Includes 2,000 restricted stock units. 401(k) plan units that represent interests in common stock; based on plan information as of February 23, 2012. There is not a one to one correlation between units and shares. Stock Options granted pursuant to the 1997 Stock Option and Incentive Plan. Represents weighted average purchase price. These shares were sold at a price ranging from $63.440 and $63.8200 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. Represents weighted average purchase price. These shares were sold at a price ranging from $63.46 and $63.93 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. /s/ Stephanie G. Heim, Attorney in Fact 2012-12-14