The company was formed through the reverse takeover of Barolo Ventures and the spinout of Osisko Gold Royalties' development assets, including the Cariboo gold project in British Columbia.
The latest offering was priced at $7.50 per unit and would be used to further develop Cariboo and advance the San Antonio gold project in Mexico towards production, as well as for general corporate purposes.
The company said it also intended to close a second tranche of up to $12 million by late January "to accommodate additional interest for the units".
"We are thrilled to have raised over C$200 million since October 2020 to capitalise Osisko Development," chair and CEO Sean Roosen said.
He took part in the latest offering, taking his holdings from 93,333 shares, 46,666 warrants and 267,400 options to 106,333, 53,166 and 267,400 respectively, representing about 0.1% of the issued and outstanding shares.
"The proceeds that we've raised, coupled with our equity investments and expected near-term cash flows, forms the foundation of continued development of the Cariboo gold project," he said.
The company's flagship asset is advancing through permitting for a 4,750 tonne per day operation and Osisko Development said a feasibility study was on track for completion in the second half of 2021.
Previously-mined Cariboo has a measured and indicated 3.2 million ounce resource and an inferred 2.7Moz.
In the month since becoming Osisko Development, its shares (TSXV: ODV) have ranged from $7.01 to a high of $8.50 last week.
They closed down 2.1% on Friday to $8.22, to capitalise it at almost $978 million (US$766 million).