Company Update

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 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): December 29, 2020     GATX Corporation (Exact name of registrant as specified in its charter)       New York   1-2328   36-1124040 (State or other jurisdiction of incorporation)   (Commission File Number)   (IRS Employer Identification No.) 233 South Wacker Drive Chicago , Illinois 60606-7147 (Address of principal executive offices, including zip code) (312) 621-6200 (Registrant’s telephone number, including area code)     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:     ☐ Written communication pursuant to Rule 425 under the Securities Act (17 CFR 230.425)     ☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)     ☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))     ☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) 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 Stock   GATX   New York Stock Exchange     Chicago Stock Exchange 5.625% Senior Notes due 2066   GMTA   New York Stock Exchange 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   ☐ 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.  ☐       Item 8.01 Other Events On December 29, 2020, GATX Corporation (the “ Company ”) acquired Trifleet Leasing Holding B.V., and its owned and managed fleet of over 18,000 tank containers. A press release announcing the acquisition was issued and is filed herewith as Exhibit 99.1 and is incorporated by reference herein.   Item 9.01. Financial Statements and Exhibits. (d) Exhibits   Exhibit No.    Description 99.1    Press Release issued by the Company and dated December 30, 2020 104    Cover Page Interactive Data File (embedded within the Inline XBRL document). SIGNATURE 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.   GATX CORPORATION (Registrant) /s/ Thomas A. Ellman Thomas A. Ellman Executive Vice President and Chief Financial Officer December 30, 2020