4 1 psb844033.txt PS BUSINESS PARKS, INC. +--------+ | FORM 4 | U.S. SECURITIES AND EXCHANGE COMMISSION +--------+ WASHINGTON, D.C. 20549 [_] Check this box if no longer subject STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP to Section 16. Form 4 or Form 5 Filed pursuant to Section 16(a) of the Securities obligations may Exchange Act of 1934, Section 17(a) of the continue. See Public Utility Holding Company Act of 1935 or Instruction 1(b). Section 30(f) of the Investment Company Act of 1940 (Print or Type Responses) -------------------------------------------------------------------------------- 1. Name and Address of Reporting Person* Acquiport Two Corporation -------------------------------------------------------------------------------- (Last) (First) (Middle) c/o Heitman Capital Management LLC 180 North LaSalle St., Suite 3600 -------------------------------------------------------------------------------- (Street) Chicago, IL 60601 -------------------------------------------------------------------------------- (City) (State) (Zip) 2. Issuer Name and Ticker or Trading Symbol PS Business Parks, Inc.(PSB) ----------------------------------- 3. I.R.S. Identification Number of Reporting Person, if an entity (voluntary) 22-2909230 4. Statement for Month/Year May/2002 --------------------------------------------------- 5. If Amendment, Date of Original (Month/Year) --------------------------------- 6. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director Officer X 10% Owner Other --- --- (give title below) --- --- (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

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. * If this form is filed by more than one reporting person, see Instruction 4(b)(v). Table II--Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

Table II--Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

Explanation of Responses: (1) Shares held in the name of Acquiport Two Corporation, a 100% owned subsidiary of New York State Common Retirement Fund. ACQUIPORT TWO CORPORATION By: /s/ David B. Perisho June 10, 2002 ------------------------------- ----------------- **Signature of Reporting Person Date David B. Perisho Vice President ** 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. Joint Filer Statement Name: New York Common Retirement Fund Address: 633 Third Avenue, 31st Floor New York, NY 10017-6754 Designated Filer: Acquiport Two Corporation Issuer and Ticker Symbol: PS Business Parks, Inc. (PSB) Date of Event Requiring Statement: May, 2002 Signature: Comptroller of the State of New York as Trustee of the Common Retirement Fund By: /s/ Bruce E. Feig -------------------------- Bruce E. Feig Title: First Deputy Controller

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