Constellation Acquisition Corp I (CSTAF) uses final SPAC extension to January 29, 2026

Rhea-AI Filing Summary

Constellation Acquisition Corp I disclosed that it borrowed $5,000 under an existing unsecured promissory note from Constellation Sponsor LP and deposited these funds into its trust account for public shareholders. This small loan funds an "Extension" that moves the deadline to complete the company’s initial business combination from December 29, 2025 to January 29, 2026. The filing states this is the last of eleven one‑month extensions allowed under the company’s governing documents, giving one final month to close a deal instead of liquidating. The note bears no interest and is intended to be repaid when a business combination closes; if no deal is completed, repayment would only come from cash remaining outside the trust account, if any.

Insights

SPAC structure and capital markets analyst

Constellation uses a final one‑month SPAC extension funded by a small sponsor loan.

Constellation Acquisition Corp I has drawn $5,000 under an unsecured promissory note with its sponsor and placed the funds into the trust account to secure a one‑month deadline move to January 29, 2026. This is described as the last of eleven permitted one‑month extensions under its amended and restated memorandum and articles of association.

The note carries no interest and matures upon closing of the initial business combination, aligning repayment with a successful deal rather than ongoing operations. If the SPAC fails to consummate a combination, the note is repayable only from amounts remaining outside the trust account, reflecting the usual protection of public shareholders’ trust funds.

For investors, the key point is that the vehicle now has one final month to complete a transaction instead of facing an imminent deadline in late December 2025. Actual outcomes will depend on whether a suitable business combination can be closed by the new January 29, 2026 outside deadline.

8-K Event Classification

Item 2.03 — Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement

1 item

Item 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement Financial

The company incurred a new significant debt or off-balance-sheet obligation.

Understanding 8-K Material Events →

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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 23, 2025

CONSTELLATION ACQUISITION CORP I

(Exact name of registrant as specified in its charter)

Cayman Islands		001-39945		98-1574835
(State or other jurisdiction of incorporation)		(Commission File Number)		(IRS Employer Identification No.)

1290 Avenue of the Americas 10th Floor New York, NY		10104
(Address of principal executive offices)		(Zip Code)

(212) 983-1602

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:

☐ Written communications 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
Class A ordinary shares, par value $0.0001 per share		CSTAF		OTCID® Basic Market
Redeemable warrants, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50		CSTWF		OTCID® Basic Market
Units, each consisting of one Class A ordinary share and one-third of one redeemable warrant		CSTUF		OTCID® Basic Market

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 2.03. Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement or a Registrant.

On December 23, 2025, Constellation Acquisition Corp I (the “Company”) drew an aggregate of $5,000 (the “Extension Funds”), as approved by unanimous resolution of the extension committee of the Company’s board of directors, dated December 23, 2025, pursuant to the unsecured promissory note, dated January 30, 2024 between the Company and Constellation Sponsor LP (the “Note”), which Extension Funds the Company deposited into the Company’s trust account for its public shareholders. This deposit enables the Company to extend the date by which it must complete its initial business combination from December 29, 2025 to January 29, 2026 (the “Extension”). The Extension is the last of eleven one-month extensions permitted under the Company’s amended and restated memorandum and articles of association and provides the Company with additional time to complete its initial business combination. The Note does not bear interest and matures upon closing of the Company’s initial business combination. In the event that the Company does not consummate a business combination, the Note will be repaid only from amounts remaining outside of the Company’s trust account, if any.

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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: December 29, 2025

	CONSTELLATION ACQUISITION CORP I
	By:	/s/ Chandra R. Patel
	Name:	Chandra R. Patel
	Title:	Chief Executive Officer

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FAQ

What did Constellation Acquisition Corp I (CSTAF) announce in this 8-K?

Constellation Acquisition Corp I reported that it drew $5,000 under an unsecured promissory note with Constellation Sponsor LP and deposited the funds into its trust account, allowing it to extend the deadline to complete its initial business combination by one month.

How long did CSTAF extend its business combination deadline and to what date?

The company extended its deadline to complete an initial business combination by one month, moving it from December 29, 2025 to January 29, 2026.

Is this the last extension available to Constellation Acquisition Corp I (CSTAF)?

Yes. The filing states that this Extension is the last of eleven one-month extensions permitted under the company’s amended and restated memorandum and articles of association.

What are the key terms of the promissory note used for CSTAFs extension?

The unsecured promissory note, dated January 30, 2024 between the company and Constellation Sponsor LP, provides $5,000 of Extension Funds, bears no interest, and matures upon closing of the companys initial business combination.

How will the $5,000 extension funds for CSTAF be repaid if no deal occurs?

If the company does not consummate a business combination, the filing states that the note will be repaid only from amounts remaining outside the companys trust account, if any.

Where were the CSTAF extension funds deposited?

The $5,000 of Extension Funds were deposited into the companys trust account for its public shareholders, as described in the filing.