AmBase Corp

This Proxy Statement is furnished in connection with the solicitation by the Board of Directors of AmBase Corporation (the “Company”) of proxies to be voted at the Annual Meeting of Stockholders of the Company (the “Annual Meeting”) to be held at the Sheraton Tarrytown Hotel, 600 White Plains Road, Tarrytown, New York at 9:00 a.m., Eastern Daylight Time, on Friday, June 6, 2025, and at any adjournment or postponement thereof. This Proxy Statement and the accompanying proxy are being mailed to stockholders commencing on or about the Record Date.

Shares represented by a duly executed proxy in the accompanying form received by the Company prior to the Annual Meeting will be voted on at the Annual Meeting in accordance with instructions given by the stockholder in the proxy. Any stockholder granting a proxy may revoke it at any time before it is exercised by granting a proxy bearing a later date, by giving notice in writing to the Secretary of the Company or by voting in person at the Annual Meeting.

At the Annual Meeting, the stockholders will be asked: (i) to elect Mr. Richard A. Bianco, Jr. and Mr. Scott M. Salant as director(s) of the Company to serve three-year terms ending in 2027; and until their successor is elected and qualified or until their earlier resignation, removal or death; and (ii) to ratify the approval of the appointment of Marcum LLP as the Company’s independent registered public accounting firm for the year ending December 31, 2025.

The persons acting under the accompanying proxy have been designated by the Board of Directors and, unless contrary instructions are given, will vote the shares represented by a properly executed proxy (i) for the election of the nominee(s) for director(s) named above; and (ii) for the approval of the appointment of Marcum LLP as the Company’s independent registered public accounting firm.

If a stockholder is not the record holder, such as where the shares are held through a broker, bank or other financial institution, the stockholder must provide voting instructions to the record holder of the shares in accordance with the record holder’s requirements in order to ensure the shares are properly voted. Your broker will not be permitted to vote on your behalf on the election of the director(s) unless you provide specific instructions by completing and returning the voting instruction form or following the instructions provided to you to vote your shares. For your vote to be counted, you now will need to communicate your voting decisions to your broker, bank or other financial institution before the date of the stockholders meeting.

The close of business on Thursday, April 17, 2025, has been fixed by the Board of Directors as the record date for the determination of stockholders entitled to notice of and to vote at the Annual Meeting or any adjournments thereof. Only the holders of record of common stock of the Company, par value $0.01 per share (the “Common Stock”) at the close of business on the record date, are entitled to vote on the matters presented at the Annual Meeting. Each share of Common Stock entitles the holder to one vote on each matter presented at the Annual Meeting. As of March 24, 2025, there were approximately 84,938,000 shares of Common Stock issued and outstanding. The holders of a majority of the outstanding shares of Common Stock entitled to vote at the Annual Meeting shall constitute a quorum. If there is less than a quorum, a majority of those present in person or by proxy may adjourn the Annual Meeting. A plurality vote of the holders of the shares of Common Stock represented in person or by proxy and voting at the Annual Meeting, a quorum being present, is required for the election of the director(s). The affirmative vote of the holders of a majority of the shares of Common Stock represented in person or by proxy and voting at the Annual Meeting, a quorum being present, is necessary for the ratification of the appointment of Marcum LLP as the Company’s independent registered public accounting firm.

Abstentions, votes withheld and shares not voted, including broker non-votes, are not included in determining the number of votes cast for the election of the director(s); or for the approval of Marcum LLP as the Company’s independent registered public accounting firm. Abstentions, votes withheld and broker non-votes, are counted for purposes of determining whether a quorum is present at the Annual Meeting.