Exhibit 99.1

 

OSISKO DEVELOPMENT CORP.

 

Report of Voting Results Pursuant to Section 11.3 of
National Instrument 51-102 – Continuous Disclosure Obligations

 

This report sets forth a brief description of each matter that was voted upon at the annual and special meeting of holders of common shares of Osisko Development Corp. (the “Company") held on June 23, 2026 (the “Meeting") and the outcome of the vote. Further information regarding the business of the Meeting is contained in the Company's management information circular dated May 11, 2026 (the “Circular"), which is available on SEDAR+ (www.sedarplus.ca) under the Company's issuer profile.

 

1.Election of Directors

 

Each of the seven director nominees proposed by management were elected. Voting was conducted by ballot. The voting results were as follows:

 

Nominee  Votes For   % of Votes For   Votes Against   % of Votes
Against		 
Sean Roosen   202,062,275    98.91%   2,234,846    1.09%
Charles E. Page   172,497,611    84.44%   31,799,510    15.56%
Michèle McCarthy   171,284,316    83.84%   33,012,804    16.16%
David Danziger   169,832,493    83.13%   34,464,628    16.87%
Stephen Quin   203,529,000    99.62%   768,121    0.38%
Susan Craig   203,517,931    99.62%   779,189    0.38%
Keith McKay   203,583,947    99.65%   713,174    0.35%

 

2.Appointment of Auditors

 

PricewaterhouseCoopers LLP was approved to serve as the auditor of the Company for 2026 and at a remuneration to be fixed by the board of directors. Voting was conducted by show of hands. The voting results were as follows:

 

Votes For   % of Votes For   Votes Withheld   % of Votes Withheld 
 225,812,331    99.90%   219,606    0.10%

 

3.Registered Office Resolution

 

The special resolution (the full text of which is reproduced in the Circular) for the amendment to the Articles of the Company to change the province of the Company's registered office from the Province of Québec to the Province of Ontario was approved. Voting was conducted by show of hands. The voting results were as follows:

 

Votes For   % of Votes For   Votes Against   % of Votes Against 
 204,029,595    99.88%   241,093    0.12%

 

4.Name Change Resolution

 

The special resolution (the full text of which is reproduced in the Circular) for the change of name of the Company from “Osisko Development Corp." to “Osisko Gold Group Inc." was approved. Voting was conducted by show of hands. The voting results were as follows:

 

Votes For   % of Votes For   Votes Against   % of Votes Against 
 224,810,764    99.46%   1,221,172    0.54%

 

Dated at Toronto, Ontario, this 23rd day of June 2026.