Lawsuit Settlement Prevents Goldcorp Take-Up and Payment Prior to April 15, 2014

MONTREAL, QUEBEC--(Marketwired - March 21, 2014) - Osisko Mining Corporation ("Osisko" or the "Corporation") (TSX:OSK)(FRANKFURT:EWX) noted the announcement by Goldcorp Inc. ("Goldcorp") today that it has extended its hostile take-over bid which was commenced January 14, 2014, until April 4th, 2014. Osisko reminds shareholders that, pursuant to the settlement agreement entered into by Goldcorp and Osisko, Goldcorp is prohibited from taking up and paying for any Osisko shares deposited to its hostile take-over bid prior to April 15, 2014.

The Goldcorp offer continues to be highly conditional. Until April 15, 2014, absent intervening events, Osisko shareholders should expect to receive further extensions from Goldcorp in addition to communications with respect to the waiver or satisfaction of the numerous conditions to the Goldcorp offer.

Osisko is continuing to manage a robust process to aggressively pursue a range of value maximizing alternatives that are in the best interests of Osisko, the Osisko shareholders and other stakeholders. The settlement contemplates that the deadlines described above may be abbreviated if Osisko announces a value maximizing alternative to Goldcorp's hostile bid prior to April 15, 2014.

Reject the Inadequate Goldcorp Offer

As previously disclosed, the Osisko Board of Directors has unanimously recommended that Osisko shareholders reject the hostile take-over bid initiated by Goldcorp and not tender their Osisko shares to the Goldcorp offer. The Osisko Board determined that the Goldcorp offer fails to adequately compensate Osisko shareholders for, among others things, the strategic value of Osisko's world-class asset base, the significant upside potential of Osisko's Canadian Malartic Mine, or the increased risk inherent in Goldcorp common shares. The full basis for the Osisko Board's recommendation is available in a Directors' Circular, a copy of which is available online at www.osisko.com.

Shareholders who have questions or who may have already tendered their shares to the Goldcorp Offer and wish to withdraw them, may do so by contacting our Information Agent, Laurel Hill Advisory Group at:

North American Toll Free: 1-877-452-7184

Banks, Brokers or collect calls: 416-304-2011

Email: assistance@laurelhill.com

About Osisko Mining Corporation

Osisko Mining Corporation operates the Canadian Malartic Gold Mine in Malartic, Quebec and is pursuing exploration on a number of properties in Ontario and Mexico.

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 including, without limitation, the possibility of any business combination being proposed, the results of any review of any such proposal. Although the Corporation believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, including, without limitation that any business combination transaction will ultimately be proposed, the results of the review of any such proposal, 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 the content of any business combination proposal, gold prices, the Corporation's limited experience with production and development stage mining operations, uninsured risks, regulatory changes or sanctions, defects in titles, 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.