Erp Operating LTD Partnership 10-Q 2002 Q3 Quarterly report

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Exhibit 99.1

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        In connection with the Quarterly Report of ERP Operating Limited Partnership (the "Company") on Form 10-Q for the period ending September 30, 2002 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Douglas Crocker II, Chief Executive Officer of the General Partner of the Company, certify, pursuant to 18.U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that, to the best of my knowledge:

        (1)    The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

        (2)    The information contained in the Report fairly presents, in all material respects, the financial condition and result of operations of the Company.

/s/  DOUGLAS CROCKER II      Douglas Crocker II
Chief Executive Officer of
Equity Residential, General Partner
November 13, 2002

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Exhibit 99.1