UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC  20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of

the Securities Exchange Act of 1934

Date of report (Date of earliest event reported): September 10, 2020

CORPORATE OFFICE PROPERTIES TRUST

CORPORATE OFFICE PROPERTIES, L.P.

(Exact name of registrant as specified in its charter)

6711 Columbia Gateway Drive, Suite 300

Columbia, Maryland 21046

(Address of principal executive offices)

(443) 285-5400

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2 below):

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging Growth Company (Corporate Office Properties Trust) ¨

Emerging Growth Company (Corporate Office Properties, L.P.) ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Corporate Office Properties Trust ¨

Corporate Office Properties, L.P. ¨

On September 16, 2020, Corporate Office Properties Trust (“COPT”) issued a press release announcing the pricing of the previously announced cash tender offer for any and all of the outstanding 3.700% Senior Notes due 2021 of Corporate Office Properties, L.P. (“COPLP”), fully and unconditionally guaranteed by COPT.

A copy of the press release is furnished as Exhibit 99.1 hereto and is incorporated by reference herein.

The information included in Item 7.01 of this Current Report on Form 8-K, including Exhibit 99.1 and the information contained once accessible through the website indicated above, is being “furnished” and shall not be deemed “filed” for the purposes of or otherwise subject to liabilities under Section 18 of the Securities Exchange Act of 1934, as amended, and shall not be deemed to be incorporated by reference into the filings of COPT or COPLP under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended.

On September 10, 2020, COPT and COPLP entered into an underwriting agreement (the “Underwriting Agreement”) by and among themselves and Wells Fargo Securities, LLC and J.P. Morgan Securities LLC, acting on behalf of themselves and as representatives of the several underwriters listed on Schedule I thereto, in connection with the COPLP’s issuance and sale of $400,000,000 aggregate principal amount of 2.250% Senior Notes due 2026. COPT and COPLP filed a prospectus supplement in connection with the offering, dated September 10, 2020, filed with the Securities and Exchange Commission on September 14, 2020.

The Underwriting Agreement contains various representations, warranties and agreements by COPLP, conditions to closing, indemnification rights and obligations of the parties. The description of the Underwriting Agreement set forth above is qualified in its entirety by reference to the Underwriting Agreement, which is filed as Exhibit 1.1 to this Current Report on Form 8-K and incorporated by reference herein.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.