Mr. John Burzynski reports

GOLD FIELDS COMPLETES ACQUISITION OF OSISKO MINING

Osisko Mining Inc. has completed its previously announced plan of arrangement transaction, pursuant to which, among other things, Gold Fields Ltd., through a 100-per-cent-owned Canadian subsidiary, Gold Fields Windfall Holdings Inc., acquired all of the issued and outstanding common shares of Osisko.

Osisko's chairman and chief executive officer, John Burzynski, commented:

"This premium transaction represents a strong and near-term outcome for our shareholders and is reflective of the truly world class nature of the Windfall project. In the span of nine years, we've transformed Windfall into one of the largest and highest-grade gold development projects globally and this transaction is a testament to the extraordinary entrepreneurial effort of the Osisko Mining team. Gold Fields is a globally diversified senior gold producer with an impressive track record of successfully building and operating mines. As our (now former) joint venture partner at Windfall, Gold Fields knows the asset well and understands the significance of the strong relationships that we have built in Quebec with all of our stakeholders. Moreover, Gold Fields share our core principles of operating in a safe, inclusive and socially responsible manner. They are well suited to take Windfall into production and we wish them all the best going forward."

Under the terms of the arrangement, each former shareholder of Osisko is entitled to receive $4.90 for each share held immediately prior to the effective time of the arrangement. A final order approving the arrangement was granted by the Ontario Superior Court of Justice on Oct. 22, 2024. The arrangement became effective earlier today.

Former registered shareholders of Osisko are reminded that, in order to receive the consideration to which they are entitled under the arrangement, they must complete, sign and return the letter of transmittal to TSX Trust Company, in its capacity as depositary under the arrangement, together with their certificate(s) or DRS advice(s) representing their shares. If you have any questions or require further information regarding the procedures for receiving the consideration, please contact TSX Trust Company.

Former non-registered shareholders should receive the consideration to which they are entitled under the arrangement directly in their brokerage accounts. Non-registered shareholders should contact their broker or other intermediary if they have any questions or require further information regarding the procedures for receiving the consideration to which they are entitled under the arrangement.

As a result of the completion of the arrangement, the shares are expected to be delisted from the Toronto Stock Exchange within two business days of closing. Osisko intends to submit an application to the applicable securities regulators to cease to be a reporting issuer and to terminate its public reporting obligations. Each of the directors and senior officers of Osisko have resigned from their respective positions with Osisko upon completion of the arrangement.

Advisers

Maxit Capital LP and Canaccord Genuity Corp. acted as financial advisers to Osisko. Bennett Jones LLP acted as legal adviser to Osisko. Fort Capital Partners acted as financial adviser to the special committee of independent directors of Osisko. Cassels Brock & Blackwell LLP acted as independent legal advisers to the special committee.

About Osisko Mining Inc.

Osisko is a mineral exploration company focused on the acquisition, exploration and development of precious metal resource properties in Canada.

We seek Safe Harbor.