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): May 10, 2021

Supernova Partners Acquisition Company III, Ltd.

(Exact name of registrant as specified in its charter)

(202) 918-7050

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

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:

Securities registered pursuant to Section 12(b) of the Securities Exchange Act of 1934:

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 May 10, 2021, Supernova Partners Acquisition Company III, Ltd. (the “Company,” “us” or “our”) announced that the holders of the Company’s units sold in the Company’s initial public offering (the “Units”) may elect to separately trade the Class A ordinary shares, par value $0.0001 per share (“Class A Ordinary Shares”), and redeemable warrants included in the Units commencing on May 13, 2021. Each Unit consists of one Class A Ordinary Share and one-fifth of one redeemable warrant to purchase one Class A Ordinary Share. Any Units not separated will continue to trade on the New York Stock Exchange (the “NYSE”) under the symbol “STRE.U.” Any underlying Class A Ordinary Shares and redeemable warrants that are separated will trade on the NYSE under the symbols “STRE” and “STRE WS,” respectively. No fractional warrants will be issued upon separation of the Units and only whole warrants will trade. Holders of Units will need to have their brokers contact American Stock Transfer & Trust Company, LLC, the Company’s transfer agent, in order to separate such holders’ Units into Class A Ordinary Shares and redeemable warrants.

A copy of the press release issued by the Company announcing the separate trading of the securities underlying the Units is attached hereto as Exhibit 99.1.

This report may include “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. All statements other than statements of historical fact included in this report are forward-looking statements. When used in this report, words such as “anticipate,” “believe,” “estimate,” “expect,” “intend” and similar expressions, as they relate to us or our management team, identify forward-looking statements. Such forward-looking statements are based on the beliefs of management, as well as assumptions made by, and information currently available to, the Company’s management. Actual results could differ materially from those contemplated by the forward-looking statements as a result of certain factors detailed in the Company’s filings with the Securities and Exchange Commission (the “SEC”). All subsequent written or oral forward-looking statements attributable to us or persons acting on our behalf are qualified in their entirety by this paragraph. Forward-looking statements are subject to numerous conditions, many of which are beyond the control of the Company, including those set forth in the Risk Factors section of the Company’s registration statement and prospectus relating to the Company’s initial public offering filed with the SEC. Copies of such filings are available on the SEC’s website, www.sec.gov. The Company undertakes no obligation to update these statements for revisions or changes after the date of this report, except as required by law.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits. The following exhibits are filed with this Form 8-K:

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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.

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