Osisko Reports 34.7 Metres at 4.57 g/t Gold at Pandora

MONTREAL, QUEBEC--(Marketwired - Mar 10, 2014) - Osisko Mining Corp. ("Osisko" or the "Corporation") (TSX:OSK)(FRANKFURT:EWX) is pleased to announce initial results from the 2014 drilling program on the 100% owned Pandora property, located in the Abitibi region of Quebec, approximately 17 km northwest of the Canadian Malartic mine. The purpose of the program was to test a portion of the Cadillac-Larder Lake Fault (CLLF) for lower grade disseminated-style mineralization that could offer potential for underground or surface bulk tonnage mineralization. Highlights of the seven-hole, 1500 metre program include 45.4 metres at 1.81 g/t Au (hole PN14-03), 34.7 metres at 4.57 g/t Au (hole PN14-05) and 58.5 metres at 1.09 g/t Au (hole PN14-06). Significant assay results are summarized in the table below:

The CLLF cuts the property in a northwest-southeast direction over a distance of approximately 2 kilometres. This increases to a distance of 5.5 kilometers if the adjacent Wood-Pandora property, located to the west, is included; the latter is 50% owned by Osisko. All mineralization intersected in drilling consists of disseminated pyrite and arsenopyrite hosted by sheared biotitic and silicified metasediments. The drill program tested a 140 metre-long segment of the CLLZ located near the north-central portion of the property. Mineralization is open at depth and to the east and west. The CLLZ is approximately 100 metres wide at this location and includes alternating sheared clastic metasediments and serpentinized ultramafic rocks.

Previous work on the property has adequately evaluated the potential for higher grade vein-hosted mineralization but did not obtain significant results. Results from this preliminary drill program are encouraging and indicate potential in this sector for 1 to 3 g/t Au bulk tonnage, disseminated style mineralization within 10 to 20 metre-wide portions of sheared and mineralized lithologies in the CLLF. Further compilation of historical work and will be completed within this framework before proceeding to a more extensive phase two drill program.

All NQ core assays reported above were obtained by standard 50 g fire assaying-AA finish or gravimetric finish at ALS Chemex laboratories in Val d'Or, Quebec, an ISO/IEC guideline 17025-accredited facility. Reported drill core weighted averages were calculated using a minimum of 0.35 g/t Au over successive intervals of 10 metres with maximum internal dilution length of 10 metres. Intersections of less than 10 metres at less than 1 g/t Au are not reported. Lost core intervals, constituting less than 0.5% of reported intervals within mineralized intersections, were all less than one metre long and incorporated as the average grade of adjacent intervals above and below in all length-weighted calculations. Osisko follows strict QA-QC protocol measures in keeping with industry standards and regulatory reporting requirements. Mr. Robert Wares, D.Sc., P. Geo., Senior Vice President Exploration and Resource Development for Osisko, is the Qualified Person who has reviewed this news release and is responsible for the technical information reported herein, including verification of the data disclosed.

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 Inc. 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

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 potential for 1 to 3 g/t Au bulk tonnage, disseminated style mineralization, on the Pandora property, the continuation and success of exploration activities or the development of projects, and Osisko's view on the quality and the potential of its Canadian Malartic asset and on Goldcorp common shares. Although the Corporation believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, 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, results of exploration and development activities, 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.