ATCO Atlas Corporation

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

Form 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report: December 1, 2022

Commission File Number 001-39237

ATLAS CORP.

(Exact name of Registrant as specified in its Charter)

23 Berkeley Square

London, United Kingdom

W1J 6HE

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.    Form 20-F  ☒    Form 40-F  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101 (b)(1).     Yes  ☐    No  ☒

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101 (b)(7).     Yes  ☐    No  ☒

This report on Form 6-K of Atlas Corp., or this Report, is hereby incorporated by reference into: the Registration Statement of Atlas Corp. filed with the Securities and Exchange Commission, (the “SEC”), on May 30, 2008 on Form F-3D (Registration No. 333-151329), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on March 31, 2011 on Form S-8 (Registration No. 333-173207), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on June 20, 2013 on Form S-8 (Registration No. 333-189493), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on April 24, 2012 on Form F-3 (Registration No. 333-180895), as amended on March 22, 2013 and February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on April 29, 2014 on Form F-3 (Registration No. 333-195571), as amended on March 6, 2017, April 19, 2017 and February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on November 28, 2014 on Form F-3 (Registration No. 333-200639), as amended on March 6, 2017, April 19, 2017 and February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on November 28, 2014 on Form S-8 (Registration No. 333-200640), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on March 12, 2015 on Form F-3D (Registration No. 333-202698), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on June 24, 2016 on Form S-8 (Registration No. 333-212230), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on August 25, 2017 on Form F-3 (Registration No. 333-220176), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on December 21, 2017 on Form S-8 (Registration No. 333-222216), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on April 13, 2018 on Form F-3D (Registration No. 333-224291), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on April 13, 2018 on Form F-3 (Registration No. 333-224288), as amended on May 3, 2018, May 7, 2018 and February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on September 28, 2018 on Form F-3 (Registration No. 333-227597), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on January 18, 2019 on Form F-3 (Registration No. 333-229312), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on March 27, 2019 on Form F-3 (Registration No. 333-230524), as amended on February 28, 2020, the Registration Statement of Atlas Corp. filed with the SEC on May 11, 2020 on Form F-3 (Registration No. 333-238178), as supplemented on December 7, 2020, the Registration Statement of Atlas Corp. filed with the SEC on June 30, 2020 on Form S-8 (Registration No. 333-239578), the Registration Statement of Atlas Corp. filed with SEC on March 19, 2021 on Form F-3 (Registration No. 333-254536), the Registration Statement of Atlas Corp. filed with the SEC on July 16, 2021 on Form F-3 (Registration No. 333-257967), and the Registration Statement of Atlas Corp. filed with the SEC on March 25, 2022 on Form S-8 (Registration No. 333-263872).

Information Contained in this Form 6-K Report

On December 1, 2022, Seaspan Corporation (“Seaspan”), a wholly owned subsidiary of Atlas Corp. (the “Company”), announced that Seaspan will hold a meeting of the holders of its 6.5% sustainability-linked senior unsecured bonds due 2026 (the “NOK Bonds”) on December 16, 2022 to consider a proposal for certain amendments to the terms of the NOK Bonds (the “Amendment Proposal”). Seaspan is seeking approval of the Amendment Proposal in furtherance of the Company’s obligations pursuant to the previously announced Agreement and Plan of Merger, dated October 31, 2022, among the Company, Poseidon Acquisition Corp. and Poseidon Merger Sub, Inc.