Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q Commission File Number: 1-12252 (Equity Residential) Commission File Number: 0-24920 (ERP Operating Limited Partnership) EQUITY RESIDENTIAL ERP OPERATING LIMITED PARTNERSHIP (Exact name of registrant as specified in its charter) Maryland (Equity Residential) 13-3675988 (Equity Residential) (State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification No.) Two North Riverside P ...