SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 12b-25 Commission File Number: 1-10709 NOTIFICATION OF LATE FILING (Check One): [ ] Form 10-K [ ] Form 20-F [X] Form 11-K [ ] Form 10-Q [ ] Form N-SAR [ ] Form N-CSR For Period Ended: December 31, 2004 [ ] Transition Report on Form 10-K [ ] Transition Report on Form 10-Q [ ] Transition Report on Form 20-F [ ] Transition Report on Form N-SAR [ ] Transition Report on Form 11-K For the Transition Period Ended: ______________. Nothing in this form shall be construed to imply that the Commission has verified any information contained herein. If the notification relates to a portion of the filing checked above, identify the item(s) to which the notification relates: PART I REGISTRANT INFORMATION PS Business Parks, Inc. on behalf of the PS 401(k) Profit Sharing Plan 701 Western Avenue Glendale, CA, 91201 PART II RULE 12b-25 (b) AND (c) If the subject report could not be filed without unreasonable effort or expense and the registrant seeks relief pursuant to Rule 12b-25(b), the following should be completed. (Check box if appropriate.) [ ] (a) The reasons described in reasonable detail in Part III of this form could not be eliminated without unreasonable effort or expense; [X] (b) The subject annual report, semi-annual report, transition report on Form 10-K, Form 20-F, Form 11-K, Form N-SAR or Form N-CSR, or portion thereof, will be filed on or before the fifteenth calendar day following the prescribed due date; or the subject quarterly report or transition report on Form 10-Q, or portion thereof, will be filed on or before the fifth calendar day following the prescribed due date; and [ ] (c) The accountant's statement or other exhibit required by Rule 12b-25(c) has been attached if applicable. PART III NARRATIVE State below in reasonable detail why Forms 10-K, 20-F, 11-K, 10-Q, N-SAR, N-CSR, or the transition report or portion thereof, could not be filed within the prescribed time period. The Company is experiencing delays in obtaining information from certain service providers to the Plan to provide to the Company's external auditors for the completion of the audit report. Due to the reasons described above, the Registrant could not have timely filed the Form 11-K without unreasonable effort or expense, and the Form 11-K will be filed no later than the fifteenth calendar day following the prescribed due date. -1- PART IV OTHER INFORMATION (1) Name and telephone number of person to contact in regard to this notification: Jon Osborne - (818) 244-8080 (2) Have all other periodic reports required under Section 13 or 15(d) of the Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of 1940 during the preceding 12 months or for such shorter period that the registrant was required to file such report(s) been filed? If the answer is no, identify report(s). |X| Yes [ ] No (3) Is it anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or portion thereof? [ ] Yes |X| No If so: attach an explanation of the anticipated change, both narratively and quantitatively, and, if appropriate, state the reasons why a reasonable estimate of the results cannot be made. Not applicable. -2- PS BUSINESSPARKS, INC. on behalf of the PS 401(k) PROFIT SHARING PLAN Has caused this notification to be signed on its behalf by the undersigned thereunto duly authorized. Date: June 30, 2005 By: /s/ J. Alan Herd ----------------- J. Alan Herd Chairman, Administrative Committee -3-