APP. E4 REGULATION OF INVESTMENT ADVISORS CUSIP No._740706106 13G Page______of______Pages ________________________________________________________________________ 1. NAME OF REPORTING PERSON S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Clarion CRA Securities, LP 232802869 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a)____ (b)____ 3. SEC USE ONLY 4. CITIZENSHIP OR PLACE OF ORGANIZATION 259 N. Radnor Chester Road, Suite 205 Radnor, PA 19087 NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH 5. SOLE VOTING POWER 2,499,970 shares, sole voting power 6. SHARED VOTING POWER No shares under shared voting power 7. SOLE DISPOSITIVE POWER 3,297,200 shares, sole dispositive power 8. SHARED DISPOSITOVE POWER 28,700 shares, shared dispositive power 9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,325,900 shares 10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* 11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 7.79% 12. TYPE OF REPORTING PERSON* IA SCHEDULE 13G APP. E4 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No _______)* Prentiss Properties Trust (Name of Issuer) Common Stock (Title of Class of Securities) 740706106 (Cusip Number) Check the following box if a fee is being paid with this statement ____. (A fee is not required only if the filing person: (1) has a previous statement on file reporting beneficial ownership of more than five percent of the class of securities described in Item 1; and (2) has filed no amendment subsequent thereto reporting beneficial ownership of five percent or less of such class.) (See Rule 13d-7). *The remainder of this cover page shall be filled out for a reporting persons initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page. The information required in the remainder of this cover page shall not be deemed to be filed for the purpose of Section 18 of the Securities Exchange Act of 1934 (Act) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes). Sec 1745 (6-88) E4-1 Items Item 1 Prentiss Properties Trust 3890 W NORTHWEST HWY STE 400 DALLAS TX 75220 Item 2 (a) CRA Real Estate Securities, L.P. (b) 259 N. Radnor-Chester Road, Suite 205 Radnor, PA 19087 (c) N/A (d) Common Stock (e) 740706106 Item 3 (e) Investment Adviser registered under section 203 of the Investment (f) Advisers Act of 1940 Item 4 (a) 3,325,900 shares (b) 7.79% (c) (i.) 2,499,970 shares, sole voting power (ii.) No shares under shared voting power (iii.) 3,297,200 shares, sole dispositive power (iv.) 28,700 shares, shared dispositive power Item 5 N/A Item 6 N/A Item 7 N/A Item 8 N/A Item 9 N/A Item 10 T. Ritson Ferguson, President