Acadian Asset Management Inc.

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TABLE OF CONTENTS

CONTENTS

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934 (Amendment No. )

NOTICE OF 2025 ANNUAL MEETING OF STOCKHOLDERS

To the Holders of Common Stock of Acadian Asset Management Inc.:

Notice is hereby given that the 2025 annual meeting of stockholders (the “Annual Meeting”) of Acadian Asset Management Inc. (the “Company”) will be held at 10:30 a.m. Eastern Time on Tuesday, May 13, 2025. For convenience purposes, and to facilitate stockholder access to the Annual Meeting, we will hold the Annual Meeting in a virtual format. Stockholders as of March 19, 2025, the record date for the Annual Meeting, will be able to access, attend and participate in the live Annual Meeting webcast at meetnow.global/MY4Y5ZH. Stockholders can gain access to the Annual Meeting by accessing the link above and selecting “I have a Control Number.” Stockholders can then enter their control number shown on the notice of internet availability or proxy card previously received. If you hold shares beneficially through a bank, broker or other nominee, you must register in advance to access, attend and participate in the Annual Meeting. For additional information on how to attend the Annual Meeting, see “How do I attend the meeting, ask a question and/or vote at the meeting?” on page 4 of the accompanying proxy statement.

Details regarding the Annual Meeting, the business to be conducted at the Annual Meeting, and information about the Company that you should consider when you vote your shares of common stock of the Company, par value $0.001 per share (“Common Stock”), are described in the accompanying proxy statement.

At the Annual Meeting, you will be asked to consider and vote on the following proposals:

1. Proposal 1—Vote to elect directors of the Company:

To elect five directors to serve on the Company’s Board of Directors (the “Board”) until the Company’s 2026 Annual Meeting of Stockholders and until their respective successors are duly elected and qualified, on the following basis:

1.01—To re-elect Mr. Robert J. Chersi as a director of the Company;

1.02—To re-elect Mr. Andrew Kim as a director of the Company;

1.03—To re-elect Mr. John Paulson as a director of the Company;

1.04—To re-elect Ms. Barbara Trebbi as a director of the Company; and

1.05—To re-elect Ms. Kelly Young as a director of the Company.

2. Proposal 2—Vote regarding ratification of independent registered public accounting firm:

To ratify the appointment of KPMG LLP as the Company’s independent registered public accounting firm for the year ending December 31, 2025.

3. Proposal 3—Advisory vote on executive compensation:

To approve, on an advisory basis, the compensation of the Company’s named executive officers as described in the accompanying proxy statement under the section titled Compensation Discussion and Analysis and the tabular and narrative disclosure contained in the accompanying proxy statement.

Other business.

To transact such other business that is properly presented at the Annual Meeting and any adjournments or postponements thereof.

THE BOARD RECOMMENDS THAT YOU VOTE “FOR” EACH OF THE NOMINEES REFERENCED ABOVE AND “FOR” THE APPROVAL OF PROPOSALS 2 AND 3.

The Company is a corporation incorporated under the laws of Delaware. In accordance with the Company’s Bylaws, the election of directors shall be decided by a majority of the votes cast and all other matters shall be decided by the affirmative vote of a majority of shares present in person or represented by proxy at the Annual Meeting and entitled to vote thereon.

You may vote if you were the record owner of Common Stock at the close of business on March 19, 2025.

We are pleased to take advantage of the Securities and Exchange Commission rules that allow us to furnish proxy materials to our stockholders on the internet instead of mailing paper copies. We believe these rules allow us to provide you with the information that you need while lowering the costs of delivery and reducing the environmental impact of the Annual Meeting.

All stockholders are cordially invited to attend the Annual Meeting virtually. Whether you plan to attend the Annual Meeting virtually or not, we urge you to vote in accordance with the instructions set forth in the proxy statement and submit your proxy by the Internet, telephone or, if you received printed proxy materials, by mail in order to ensure the presence of a quorum. You may change or revoke your proxy at any time before it is voted at the Annual Meeting.

BY ORDER OF THE BOARD OF DIRECTORS

/s/ RICHARD J. HART

Richard J. HartChief Legal and Administrative Officer and Secretary

March 31, 2025