8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR Section 15(d) of theSecurities Exchange Act of 1934

Date of Report (Date of earliest event reported):January 19, 2024

CONSTELLATION ACQUISITION CORP I

(Exact name of registrant as specified in itscharter)

(646) 585-8975

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 to the registrant under any of the following provisions:

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

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 January 10, 2024, Constellation Acquisition Corp I (“Constellation”) filed a definitive proxy statement (the “Extension Proxy Statement”) for an extraordinary general meeting of its shareholders to be held on January 23, 2024, at 9:00 a.m., Eastern Time, to consider and act upon a proposal to extend the date (the “Termination Date”) by which Constellation has to consummate a business combination from January 29, 2024 to February 29, 2024 (the “Articles Extension Date”) and to allow Constellation, without another shareholder vote, to elect to extend the Termination Date to consummate a business combination on a monthly basis for up to eleven times by an additional one month each time after the Articles Extension Date to January 29, 2025, by resolution of Constellation’s board of directors, if requested by Constellation Sponsor LP, a Delaware limited partnership. The Extension Proxy Statement was mailed to Constellation shareholders of record as of December 26, 2023 on or about January 10, 2024. Shareholders may obtain a copy of the Extension Proxy Statement at the SEC’s website (www.sec.gov).

As set forth in the Extension Proxy Statement, the deadline by which Constellation public shareholders had to complete the procedures for electing to redeem their Class A ordinary shares, par value $0.0001 per share (the “Public Shares”), was 5:00 p.m., Eastern Time, on January 19, 2024 (“Redemption Deadline”). The initial number of Public Shares tendered for redemption prior to the Redemption Deadline was 3,399,900. The deadline for shareholders to withdraw previously submitted redemption requests is the Redemption Deadline, unless Constellation’s board of directors determines (in its sole discretion) to permit such withdrawal of a redemption request (which it may do in whole or in part).

Shareholders may make such request by contacting our transfer agent, Continental Stock Transfer & Trust Company, at One State Street Plaza, 30th Floor, New York, New York 10004; Attn: SPAC Redemptions; E-mail: spacredemptions@continentalstock.com.

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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.

Dated: January 22, 2024

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