VMRK: 10-Q financial filing

10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2026 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 1-12252 (Vivmark Residential) Commission File Number: 0-24920 (ERP Operating Limited Partnership) VIVMARK RESIDENTIAL ERP OPERATING LIMITED PARTNERSHIP ( Exact name of registrant as specified in its charter) Maryland (Vivmark Residential) 13-3675988 (Vivmark Residential) Illinois (ERP Operating Limited Partnership) 36-3894853 (ERP Operating Limited Partnership) (State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification No.) Two North Riverside Plaza , Chicago , Illinois 60606 ( 312 ) 474-1300 or 4040 Wilson Blvd., Suite 1000 , Arlington , Virginia 22203 ( 703 ) 329-6300 (Addresses of principal executive offices) (Zip Codes) (Registrant’s telephone number, including area code) Equity Residential (Vivmark Residential) / Not applicable (ERP Operating Limited Partnership) (Former name, former address and former fiscal year, if changed since last report) Securities registered pursuant to Section 12(b) of the Act: Title of each class Trading Symbol(s) Name of each exchange on which registered Common Shares of Beneficial Interest, $0.01 Par Value (Vivmark Residential) VMRK New York Stock Exchange 7.57% Notes due August 15, 2026 (ERP Operating Limited Partnership) N/A N/A(1) Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 mo