MONTREAL, QUEBEC -- (Marketwire) -- 11/18/09 -- Osisko Mining Corporation ("Osisko") (TSX: OSK)(FRANKFURT: EWX) is pleased to report that it has received proceeds of $241 million from the exercise of 44,232,490 of its $5.45 warrant (OSK.WT.A) which expired on November 17, 2009. Some 42,510 warrants were not exercised.

These warrants were issued as part of the February 2009 $403 million financing underwritten by a syndicate of underwriters (the "Underwriters"), led by Thomas Weisel Partners Canada Inc. and BMO Nesbitt Burns Inc., and including Dundee Securities Corporation, RBC Dominion Securities Inc., National Bank Financial Inc., Paradigm Capital Inc., Canaccord Capital Corporation, TD Securities Inc. and PI Financial Corp. Osisko issued a total of 88,550,000 units (the "Units") of the Corporation at a price of $4.55 per Unit. Each Unit consisted of one common share and one-half of one common share purchase warrant.

Sean Roosen, President and Chief Executive Officer, commented on the exercise of the warrants: "We are extremely pleased to receive the proceeds of $241 million, in addition to the recent proceeds of $39.6 million from the exercise of the $7.90 warrants, thereby providing us with one of the strongest balance sheets in our sector. We appreciate the confidence of our shareholders as we develop the Canadian Malartic Project and look to grow our asset base with high quality gold development projects."

Osisko currently has 335,474,919 shares outstanding, and cash on hand of $775 million.

About Osisko

Osisko Mining Corporation is currently developing the Canadian Malartic gold deposit and evaluating adjacent areas for a large-scale open pit, bulk-tonnage mining operation. The Canadian Malartic deposit currently represents one the biggest gold reserves in Canada for a single deposit, and is still growing through ongoing drilling on new mineralized zones. Current reserves for the Canadian Malartic property are 6.28 million ounces, plus a global measured and indicated resource of 3.65 million ounces and an inferred resource of 0.84 million ounces (including the adjacent South Barnat deposit).

Forward Looking Statements

Certain statements contained in this press release may be deemed "forward-looking statements". All statements in this release, other than statements of historical fact, that address events or developments that the Corporation expects to occur, are forward looking statements. Forward looking statements are statements that are not historical facts and are generally, but not always, identified by the words "expects", "plans", "anticipates", "believes", "intends", "estimates", "projects", "potential", "scheduled" and similar expressions, or that events or conditions "will", "would", "may", "could" or "should" occur. Although the Corporation believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, including, without limitation that all technical, economical and financial conditions will be met in order to put the Canadian Malartic Project into commercial production, such statements are not guarantees of future performance and actual results may differ materially from those in forward looking statements. Factors that could cause the actual results to differ materially from those in forward-looking statements include gold prices, access to skilled consultants, mining development and mill production personnel, results of exploration and development activities, the Corporation's limited experience with production and development stage mining operations, uninsured risks, regulatory changes, defects in title, availability of personnel, materials and equipment, timeliness of government approvals, actual performance of facilities, equipment and processes relative to specifications and expectations, unanticipated environmental impacts on operations market prices, continued availability of capital and financing and general economic, market or business conditions. These factors are discussed in greater detail in the Corporation's most recent Annual Information Form filed on SEDAR, which also provides additional general assumptions in connection with these statements. The Corporation cautions that the foregoing list of important factors is not exhaustive. Investors and others who base themselves on the Corporation's forward-looking statements should carefully consider the above factors as well as the uncertainties they represent and the risk they entail. The Corporation believes that the expectations reflected in those forward-looking statements are reasonable, but no assurance can be given that these expectations will prove to be correct and such forward-looking statements included in this press release should not be unduly relied upon. These statements speak only as of the date of this press release.