UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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): April 22, 2025 (April 22, 2025)

AMBASE CORPORATION

(Exact name of registrant as specified in its charter)

Delaware	1-07265	95-2962743
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification Number)

7857 WEST SAMPLE ROAD, SUITE 134

CORAL SPRINGS, FLORIDA 33065

(Address of principal executive offices, including zip code)

(201) 265-0169

(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 (see General Instruction A.2. below):

☐	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

None.

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 4.01

Changes in Registrant’s Certifying Accountant.

(a) Resignation of Marcum LLP as the Independent Registered Public Accounting Firm

Based on information provided by Marcum LLP (“Marcum”), the independent registered public accounting firm of AmBase Corporation (the “Company”), on November 1, 2024, CBIZ CPAs P.C. (“CBIZ CPAs”) acquired the attest business of Marcum. On April 22, 2025, the Company was notified by Marcum that Marcum resigned as the Company’s independent registered public accounting firm.

The reports of Marcum on the Company’s financial statements for the fiscal years ended December 31, 2024 and 2023 included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024, did not contain an adverse opinion or a disclaimer of opinion, nor was it qualified or modified as to uncertainty, audit scope or accounting principle, except that the reports included an explanatory paragraph relating to substantial doubt about the Company’s ability to continue as a going concern.

During the fiscal years ended December 31, 2024 and 2023 and the subsequent interim period through April 22, 2025, the date of Marcum’s resignation, there were no (1) disagreements (as defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) between the Company and Marcum on any matter of accounting principles or practices, financial statement disclosure or auditing scope or procedure that would have caused Marcum to make reference to the subject matter of such a disagreement in connection with its audit reports on the Company’s financial statements for such years, or (2) reportable events (as described in Item 304(a)(1)(v) of Regulation S-K and the related instructions).

The Company has provided Marcum with a copy of this Current Report on Form 8-K prior to its filing with the Securities and Exchange Commission (the “SEC”) and requested, in accordance with applicable practices, that Marcum furnish a letter addressed to the SEC, pursuant to Item 304(a)(3) of Regulation S-K, stating whether Marcum agrees with the statements made herein. Attached as Exhibit 16.1 is a copy of Marcum’s letter, dated April 22, 2025, stating that it agrees with such statements.

(b) Engagement of CBIZ CPAs as the New Independent Registered Public Accounting Firm

As a result of CBIZ CPAs acquisition of Marcum, Marcum declined reappointment as the Company’s Independent Registered Public Accounting Firm for fiscal year 2025.

On April 22, 2025, with the approval of the Company’s Accounting and Audit Committee, CBIZ CPAs was engaged as the Company’s new independent registered public accounting firm for the fiscal year ending December 31, 2025.

During the fiscal years ended December 31, 2024 and 2023 and the subsequent interim period through April 22, 2025, neither the Company nor anyone on its behalf consulted with CBIZ CPAs regarding (1) the application of accounting principles to a specified transaction, completed or proposed, or the type of audit opinion that might be rendered on the Company’s consolidated financial statements, and neither a written report nor oral advice was provided to the Company that CBIZ CPAs concluded was an important factor considered by the Company in reaching a decision as to any accounting, auditing or financial reporting issue, or (2) any matter that was either the subject of a disagreement (as defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) or a reportable event (as described in Item 304(a)(1)(v) of Regulation S-K).

Item 9.01

Financial Statements and Exhibits

(d) Exhibits

Exhibit Number		Exhibit Title

16.1		Letter to the SEC from Marcum dated April 22, 2025

104.1		The Cover Page from this Current Report on Form 8-K, formatted in Inline XBRL.

SIGNATURES

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.

	AMBASE CORPORATION

	By	/s/ John Ferrara
	John Ferrara
	Vice President and Chief Financial Officer and Controller
	AmBase Corporation
	Date: April 22, 2025