Osisko Receives Modified Operating Parameters at Canadian Malartic

MONTREAL, QUEBEC -- (Marketwire) -- 02/19/13 -- Osisko Mining Corporation (the "Company" or "Osisko") (TSX: OSK)(FRANKFURT: EWX) is pleased to report that it has been advised by the representatives of the Government of Quebec that conditions to its operating parameters have been modified allowing it to increase access to the northern portion of the deposit and to improve the framework for the execution of its blasting operations. The modifications allow Canadian Malartic to perform blasting sequences of up to a maximum of 15 seconds and to conduct blasting operations between 11:00 AM and noon, and 3:00 PM to 4:00 PM.

Sean Roosen, President and Chief Executive Officer of Osisko, commenting: "Our team and our consultants have worked diligently with the Ministry of Sustainable Development, Environment, Wildlife and Parks personnel to add necessary flexibility in our operating conditions while ensuring the necessary safeguards for our host community and our employees. We would like to recognize the efforts made by all parties in making these necessary modifications. With these new guidelines we are confident that Canadian Malartic will continue to advance for the benefit of all stakeholders".

The Canadian Malartic Mine employs over 600 people and is an important economic contribution to the Town of Malartic, the Abitibi-Temiscamingue region and the province of Quebec. In 2012, Osisko's salaries and purchases of goods and services totalled approximately $585 million.

About Osisko

Osisko Mining Corporation operates the Canadian Malartic Gold Mine in Malartic, Quebec and is carrying out aggressive exploration and project development elsewhere in Canada and Latin America.

Contacts:

John Burzynski

Vice-President Corporate Development

(416) 363-8653
www.osisko.com


Sylvie Prud'homme

Director of Investor Relations

(514) 735-7131

Toll Free: 1-888-674-7563