First Mining Gold Corp. — Regulatory Filings 2021

Sep 29, 2021

FIRST MINING GOLD CORP.

UNDERTAKING

To: British Columbia Securities Commission Alberta Securities Commission Financial and Consumer Affairs Authority of Saskatchewan Manitoba Securities Commission Ontario Securities Commission Autorité des marchés financiers, Québec Nova Scotia Securities Commission Financial and Consumer Services Commission (New Brunswick) Office of the Superintendent of Securities, Prince Edward Island Office of the Superintendent of Securities, Newfoundland and Labrador

Re: First Mining Gold Corp. (the “Company”) Final Short Form Base Shelf Prospectus Undertaking regarding Novel Specified Derivatives

The Company has filed with the securities regulatory authorities in each of the provinces of Canada, under the Multilateral Instrument 11-102 – Passport System and National Policy 11-202 – Process for Prospectus Reviews in Multiple Jurisdictions , a base shelf prospectus dated September 29, 2021 (the “ Prospectus ”) offering up to $100,000,000 aggregate amount of common shares, preferred shares, warrants, subscription receipts and units of the Company.

In connection with any distribution of securities under the Prospectus, the undersigned hereby undertakes that it will not distribute securities that, at the time of such distribution, are “novel” specified derivatives within the meaning of the Canadian securities rules, separately to any member of the public in Canada unless the draft prospectus supplement pertaining to the distribution of novel specified derivatives has been delivered to the regulator in substantially final form, and either (a) the regulator has confirmed acceptance of such draft prospectus supplement; or (b) 10 business days have elapsed since the date of delivery to the regulator of such draft prospectus supplement and the regulator has not provided written comments.

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51280929.2

DATED this 29[th] day of September, 2021.

FIRST MINING GOLD CORP.

By: (signed) “Samir Patel”_ ______ Name: Samir Patel Title: General Counsel & Corporate Secretary

First Mining – Undertaking re Novel Specified Derivatives