Altus Group Limited — Proxy Solicitation & Information Statement 2026

Apr 2, 2026

Altus Group Limited

Notice of Annual General and Special Meeting of Shareholders

When

May 6, 2026

10:00 a.m. (Toronto time)

Virtually

https://meetings.lumiconnect.com/400-890-200-229

Password: altus2026

Business of the meeting:

1. to receive the audited consolidated financial statements of Altus Group Limited ("Altus Group" or the "Company") for the year ended December 31, 2025 and the auditor's report thereon;
2. to elect the Company's directors;
3. to appoint Ernst & Young LLP as the Company's auditor and to authorize the Board of Directors to fix the auditor's remuneration;
4. to approve ordinary resolutions to increase the number of authorized common shares to be reserved for issuance under the Company's Long-Term Equity Incentive Plan;
5. to consider a non-binding advisory resolution on the Company's approach to executive compensation; and
6. to transact such other business as may properly come before the Annual General and Special Meeting of Shareholders or at any adjournment or postponement thereof (the "Meeting").

The items of business covered at the Meeting are discussed in more detail beginning on page 11 of the accompanying management information circular, which includes important information about the Meeting, including the items of business and voting instructions. Please read it carefully prior to voting.

Shareholders of record as of the close of business on March 25, 2026 will be entitled to receive notice of, and vote at, the Meeting. There were 39,857,533 common shares of the Company ("Common Shares") outstanding on March 25, 2026.

We use the "Notice and Access" system for delivery of our proxy materials to our shareholders. This means we will post the proxy materials on our website and on our profile on the System for Electronic Document Analysis and Retrieval + ("SEDAR+"). Accordingly, this notice of meeting and accompanying management information circular, as well as the consolidated financial statements and our management's discussion and analysis for 2025, have been posted on our website at www.altusgroup.com and on SEDAR+ at www.sedarplus.ca. Shareholders with questions about notice and access can contact Altus Group's Corporate Secretary by e-mail at corporatesecretary@altusgroup.com or TSX Trust Company at 1-800-387-0825 (toll free).

Registered shareholders can return the proxy/voting instruction by: (1) mail in the envelope provided to TSX Trust Company; (2) e-mail at proxyvote@tmx.com; (3) facsimile at 1-416-607-7964; (4) internet at www.meeting-vote.com, or (5) telephone at 1-888-489-7352 no later than May 4, 2026, 10:00 a.m. (Toronto time).

Non-registered (beneficial) shareholders should follow the instructions on the voting instruction form provided by their intermediaries with respect to the procedures to be followed for voting. The Chair of the Meeting reserves the right to accept late proxies and to waive or extend the cut-off date with or without notice but is under no obligation to accept or reject any late proxy.

If you wish to appoint a person or company other than the directors or executive officers of the Company identified in the form of proxy or voting instruction form, you must register your proxyholder as described in the accompanying management information circular. Failure to register the proxyholder with TSX Trust Company will result in the proxyholder not receiving a control number that is required to participate and vote at the Meeting, and the proxyholder will only be able to attend as a guest. Guests will be able to listen to the Meeting but will not be able to vote or ask questions.

Shareholders may obtain paper copies of the management information circular, consolidated financial statements and our management's discussion and analysis free of charge by contacting TSX Trust Company at 1-888-433-6443 (toll free), or Altus Group's Corporate Secretary by e-mail at corporatesecretary@altusgroup.com. Any shareholder wishing to obtain a paper copy of the meeting materials should submit their request no later than 10:00 a.m. on April 20, 2026 in order to receive paper copies of the meeting materials in time to

Altus Group | Management Information Circular • March 25, 2026

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vote before the Meeting. Under the notice and access provisions, meeting materials will be available for viewing on the Company's website for one year from the date of posting.

In an effort to make the Meeting more accessible to our shareholders, we are planning to hold the Meeting virtual only via live webcast at 10:00 a.m. (Toronto time) on May 6, 2026. For more information about how to attend, ask questions and vote at or prior to the Meeting, see pages 6 to 10 of the management information circular.

DATED at Toronto, Ontario, this 25th day of March, 2026.

By Order of the Board of Directors

(signed) "Terrie-Lynne Devonish"

Terrie-Lynne Devonish
Chief Legal Officer & Corporate Secretary

Altus Group | Management Information Circular • March 25, 2026