Osisko Development Corp. (TSX-V-ODV) is pleased to announce the final drilling results from the 2021 exploration and category conversion drill program campaign at its San Antonio Project in Sonora State, Mexico.

The Company is also pleased to report, further to its previously-announced non-brokered private placement of up to US$110 million of subscription receipts of the Corporation, that the Corporation expects to close a first tranche of the Non-Brokered Placement on March 4, 2022 for gross proceeds of approximately US$67.3 million of Subscription Receipts.

The Corporation has also received subscription proceeds or expressions of interest for the remaining Subscription Receipts allotted under the up to US$110 million Non-Brokered Placement, which Osisko Development expects to close, as a second tranche closing, in late March 2022. The Non-Brokered Placement is being completed on a “non-brokered” basis and no commission or finder’s fee will be paid by Osisko Development in connection therewith.

San Antonio Drill Results Summary

• A total of 27,900 meters were drilled in 177 holes in 2021. The objective of the drill program was to conduct exploration and resource drilling at a spacing of 25 meters and historic drilling validation for the three main target areas (Figure 1).
• This news releases encompasses all 6,550 meters in 33 holes from the Golfo de Oro Target: GO-DD-21-015 to GO-DD-21-174 inclusive (Figure 2) and the remaining assays from 8,050 meters in 76 holes at Sapuchi: SP-DD-21-060A to SP-DD-21-173 inclusive (Figure 4).
• Assay highlights from Golfo de Oro include 1.55 g/t Au and 2.32 g/t Ag over 42.50 meters in hole GO-DD-21-111 and 2.47 g/t Au and 18.67 g/t Ag over 21.20 meters in hole GO-DD-21-057 including a sample of 18.00 g/t Au and 43.90 g/t Ag over 1.50 meters within the prospective hydrothermal breccia (Figure 2).
• Assay highlights from Sapuchi include 2.19 g/t Au and 4.12 g/t Ag over 78.90 meters in hole SP-DD-21-102 including a high-grade sample of 21.30 g/t Au and 11.75 g/t Ag over 3.20 meters (Figure 4).
• A total of 18 intervals below assayed greater than 1.00 g/t Au over at least 10.0 meters.
• Gold mineralization is hosted within altered hydrothermal breccia and sediments, as stockwork quartz veins and veinlets and adjacent to intrusions and fault structures.
• Detailed drilling results are presented in Table 1, drillhole locations are presented in Table 2, and drillhole cross sections are presented in Figures 3 and 5.

Assay Highlights

Sean Roosen, CEO of Osisko Development commented, “The 2021 diamond drill campaign at our San Antonio Project was successful in defining and expanding the known zones as shown by these recent results. The Sapuchi, Golfo de Oro, and California Zones trend for approximately three kilometers and there are at least a dozen other targets at surface that remain unexplored or underexplored along a ten kilometer strike. These results will be incorporated into the mineral resource estimate and used to further determine our next steps for expansion on the project.”

The San Antonio Project gold mineralization is characterized by hydrothermal breccia that forms an approximately 3,000 m long east-northeast trending mineralization corridor with the Luz del Cobre copper deposit at the east. The gold mineralization is associated with intense chlorite and carbonate alteration and is intrusion related with host sedimentary rocks. The breccia has been defined to a vertical depth of 500 meters and at an average depth of 250 meters. Drilling has occurred within the three major zones at Sapuchi, Golfo de Oro and California, over a combined strike length of 1 kilometer of the 3 kilometer breccia trend.

True widths are estimated to be 80% to 100% of reported core length intervals. Intervals not recovered by drilling were assigned zero grade. Top cuts have not been applied to high grade assays. Complete assay highlights are presented in Table 1, drill hole locations are listed in Table 2.

Figure 1: San Antonio Mineral Zones overview map is available at:

https://www.globenewswire.com/NewsRoom/AttachmentNg/86320f50-7bff-4628-9090-49ed8916b02b

Figure 2: Golfo de Oro plan map with select drilling highlights is available at:

https://www.globenewswire.com/NewsRoom/AttachmentNg/a86a23db-97d0-4018-a3ec-2f1a53474e49

Figure 3: Golfo de Oro section select drilling highlights is available at:

https://www.globenewswire.com/NewsRoom/AttachmentNg/26ce51cd-0d27-4b29-a62d-98be6dd40518

Figure 4: Sapuchi plan map with select drilling highlights is available at:

https://www.globenewswire.com/NewsRoom/AttachmentNg/ae5e5836-7f08-4701-92d4-26d64a4cfdbe

Figure 5: Sapuchi section select drilling highlights is available at:

https://www.globenewswire.com/NewsRoom/AttachmentNg/43cf7bc3-3230-4e5f-94bc-caa9df40f483

Qualified Persons

Maggie Layman, P.Geo. Vice President Exploration of Osisko Development, and a “qualified person” for purposes of National Instrument 43-101 – Standards of Disclosure for Mineral Projects, has prepared, validated, and approved the scientific and technical content in this news release.

Quality Assurance – Quality Control

Once received from the drill and processed, all drill core samples are sawn in half, labelled and bagged. The remaining drill core is subsequently stored on site at a secured facility at the project site. Numbered security tags are applied to lab shipments for chain of custody requirements. Quality control (QC) samples are inserted at regular intervals in the sample stream, including blanks and reference materials with all sample shipments to monitor laboratory performance.

Drill core samples are submitted to ALS Geochemistry and Bureau Veritas (BV) preparation laboratory in Hermosillo and then sent to their analytical facilities in North Vancouver, British Columbia for analysis. The facilities are accredited to the ISO/IEC 17025 standard for gold assays and all analytical methods include quality control materials at set frequencies with established data acceptance criteria. The entire sample is crushed, and 200 grams is pulverized. Analytical packages for ALS and BV are AA24 and FA450 respectively. Multi Element geochemistry is also analyzed with ME MS61 at ALS and MA 200 at BV.

About Osisko Development Corp.

Osisko Development Corp. is uniquely positioned as a premier gold development company in North America to advance the Cariboo Gold Project and other Canadian and Mexican properties, with the objective of becoming the next mid-tier gold producer. The Cariboo Gold Project, located in central British Columbia, is Osisko Development’s flagship asset with measured and indicated resources of 21.44 Mt at 4.6 Au g/t for a total of 3.2 million ounces of gold and inferred resource of 21.69 Mt at 3.9 Au g/t for a total of 2.7 million ounces of gold (see NI 43-101 Technical Report and mineral resource estimate effective October 5, 2020). The considerable exploration potential at depth and along strike distinguishes the Cariboo Gold Project relative to other development assets as does the historically low, all-in discovery costs of US $19 per ounce. The Cariboo Gold Project is advancing through permitting as a 4,750 tonnes per day underground operation with a feasibility study on track for completion in the first half of 2022. Osisko Development’s project pipeline is complemented by potential near-term production targeted from the San Antonio gold project, located in Sonora Mexico. Osisko Development began trading on the TSX Venture Exchange under the symbol “ODV” on December 2, 2020 and the Company’s 14,789,373 outstanding share purchase warrants were listed on the TSX Venture Exchange under the symbol “ODV.WT” on October 25, 2021.

Table 1: San Antonio Gold Project 2021 Length Weighted Drill Hole Gold and Silver Composites from Golfo de Oro and Sapuchi Zones

Table 2: Drill Hole Locations and Orientations