Risk Factors Dashboard

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These risks are not exhaustive. Because of these risks and other uncertainties, our actual results, performance or achievements, or industry results, may be materially different from the anticipated or estimated results discussed in the forward-looking statements in this Annual Report. New risk factors emerge from time to time, and it is not possible for our management to predict all risk factors nor can we assess the effects of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in, or implied by, any forward-looking statements. Our past results of operations are not necessarily indicative of our future results. You should not rely on any forward-looking statements, which represent our beliefs, assumptions and estimates only as of the dates on which they were made, as predictions of future events. We undertake no obligation to update these forward-looking statements, even though circumstances may change in the future, except as required under applicable securities laws. We qualify all of our forward-looking statements by these cautionary statements.

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GLOSSARY OF TECHNICAL TERMS

Conversion Factors

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The following is a glossary of certain terms used in this Annual Report:

ASAOC means Administrative Settlement Agreement and Order on Consent.

Assay means, in economic geology, to analyze the proportions of metal in a rock or overburden sample; to test an ore or mineral for composition, purity, weight or other properties of commercial interest.

BCBCA means Business Corporations Act (British Columbia).

CERCLA means Comprehensive Environmental Response, Compensation, and Liability Act, referenced informally as “Superfund.”

CWA means Clean Water Act.

DEIS means Draft Environmental Impact Statement.

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Deposit means a mineralized body which has been physically delineated by sufficient drilling, trenching and/or underground work, and found to contain a sufficient average grade of metal or metals to warrant further exploration and/or development expenditures; such a deposit does not qualify as a commercially mineable ore body or as containing ore reserves, until final legal, technical and economic factors have been resolved.

DOTC means Department of Defense Ordnance Technology Consortium.

DOW means United States Department of War.

DPA means Defense Production Act.

DROD means Draft Record of Decision.

EPCM means Engineering, Procurement and Construction Management.

FEIS means Final Environmental Impact Statement.

g/t Au means grams of gold per metric tonne of material.

Grade or grade means the amount of valuable metal in each tonne of ore, expressed as grams per tonne (g/t) for precious metals and as percent (%) for antimony.

IPDES means Idaho Pollutant Discharge Elimination System.

IBEQ means Idaho Board of Environmental Quality.

IDEQ means Idaho Department of Environmental Quality.

IDL means Idaho Department of Lands.

IDWR means Idaho Department of Water Resources.

km means kilometre(s).

m means metre(s) (equivalent to 3.281 feet).

M means million.

Mineralization or mineralization means the concentration of metals and their chemical compounds within a body of rock.

Mineral Reserve or mineral reserve means an estimate of tonnage and grade or quality of indicated and measured mineral resources that, in the opinion of the qualified person, can be the basis of an economically viable project. More specifically, it is the economically mineable part of a measured or indicated mineral resource, which includes diluting materials and allowances for losses that may occur when the material is mined or extracted.

Mineral Resource or mineral resource means a concentration or occurrence of material of economic interest in or on the Earth’s crust in such form, grade or quality, and quantity that there are reasonable prospects for economic extraction. A mineral resource is a reasonable estimate of mineralization, taking into account relevant factors such as cut-off grade, likely mining dimensions, location or continuity, that, with the assumed and justifiable technical and economic conditions, is likely to, in whole or in part, become economically extractable. It is not merely an inventory of all mineralization drilled or sampled.

MSHA means United States Department of Labor’s Mine and Safety Health Administration.

NEPA means National Environmental Policy Act.

Ore means a mineral reserve of sufficient value as to quality and quantity to enable it to be mined at a profit.

Ounce or oz means a troy ounce or twenty penny weights or 480 grains and is equivalent to 31.1035 grams.

OTIA means Ordnance Technology Initiative Agreement.

OTP means Option to Purchase.

Oz/t or oz/st means a troy ounce per short ton.

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PTC means Permit to Construct.

RACR means Removal Action Completion Report.

ROD means Record of Decision.

Sampling or sampling means a technique for collecting representative sub-volumes from a larger volume of geological material. The particular sampling method employed depends on the nature of the material being sampled and the kind of information required.

SDEIS means Supplemental Draft Environmental Impact Statement.

TIA means Technology Investment Agreement.

TSF means Tailings Storage Facility.

U.S. EPA means United States Environmental Protection Agency.

U.S. EXIM means Export-Import Bank of the United States.

USACE or Army Corps means United States Army Corps of Engineers.

USDA means United States Department of Agriculture.

USFS or Forest Service means the United States Forest Service.

NOTICE REGARDING MINING PROPERTY DISCLOSURE RULES

The material scientific and technical information in respect of the Stibnite Gold Project in this Annual Report, unless otherwise indicated, is based upon information contained in the Technical Report Summary (the “TRS”), dated as of December 31, 2025, developed for the Stibnite Gold Project in accordance with the mining property disclosure rules specified in Regulation S-K subpart 1300 (“S-K 1300”) promulgated by the U.S. Securities and Exchange Commission (the “SEC”). The TRS provides a summary of the work completed on the Project to date and updates the Technical Report Summary (the “2022 TRS”), dated as of December 31, 2021, and amended as of June 6, 2022. Updates since the 2022 TRS primarily relate to permitting, exploration drilling, engineering, land management, and financial analyses.

Any Mineral Reserves and Mineral Resources reported in the TRS by the Corporation in accordance with S-K 1300 may not qualify as such under, or may differ from, those prepared in accordance with National Instrument 43-101 - Standards of Disclosure for Mineral Projects (“NI 43-101”). Accordingly, information included or incorporated by reference in this Annual Report concerning descriptions of mineralization and estimates of Mineral Reserves and Mineral Resources under U.S. standards may not be comparable to similar information made public by Canadian companies in accordance with the reporting and disclosure requirements of NI 43-101.

The TRS is intended to be read as a whole and sections should not be read or relied upon out of context.

All disclosures contained in this Annual Report regarding the Mineral Reserve and Mineral Resource estimates and economic analysis on the property are fully qualified by the full disclosure contained in the TRS.

Information of a scientific or technical nature in this Annual Report have been approved by Christopher Dail, AIPG CPG #10596, Exploration Manager for Perpetua Resources Idaho, Inc. and James Norine, P.E., Senior Vice President, Projects for Perpetua Resources Idaho, Inc., and each meet the qualifications to be a “qualified person” as defined in S-K 1300.

See also “Cautionary Note Regarding Forward-Looking Statements.”

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PART I

Item 1. Business

Overview

The Corporation was incorporated under the BCBCA on February 22, 2011 under the name “Midas Gold Corp.” The Corporation changed its name to “Perpetua Resources Corp.” on February 15, 2021.

The Corporation’s head office is located at Suite 201 – 405 South 8^th Street, Boise, Idaho, U.S.A. 83702 and its registered and records office is located at Suite 1008 – 550 Burrard Street, Vancouver, British Columbia V6C 2B5.

The Corporation is engaged in acquiring mining properties with the intention of exploring, evaluating, developing and placing them into production, if warranted. The Corporation’s principal mineral project is the Stibnite Gold Project (the “Project”) in Idaho, USA, which contains several gold, silver and antimony mineral deposits. The Corporation’s current focus is to redevelop three of the Deposits known as the Hangar Flats Deposit, West End Deposit and Yellow Pine Deposit, all of which are located within the Stibnite Gold Project, as well as reprocess certain historical tailings located on the Project. These development activities are intended to be undertaken in conjunction with a major restoration program designed to address legacy impacts related to historical mining activities in the Project area.

The Corporation’s subsidiaries’ hold the properties of the Stibnite Gold Project which are comprised of a contiguous package of unpatented federal lode claims, unpatented federal mill sites, patented lode mining claims and patented mill sites. As of December 31, 2025, this land position encompassed approximately 28,536 acres held in 1,674 unpatented lode claims and mill sites and patented land holdings. A subsidiary of the Corporation acquired these rights through a combination of purchases and transactions and staking under the 1872 Mining Law and holds a portion under an option agreement. Bureau of Land Management claim rental payments and filings are current as of the date of this filing and the claims are all held in good standing.

Construction of the Stibnite Gold Project and continuing exploration and development at and around the Project are expected to constitute the principal business of the Corporation for the coming years. In the course of realizing its objectives, the Corporation expects to enter into various agreements specific to the construction, development, financing and operation of the Project, as well as agreements to process or sell products.

On January 3, 2025, the USFS issued its ROD approving the 2021 Modified Mine Plan. On May 19, 2025, the USACE issued its ROD for the CWA Section 404 permit. Following receipt of the USFS ROD and USACE CWA Section 404 permit, the USFS approved the Plan of Operations, which is based on the ROD and the Modified Mine Plan, for the Project in October 2025. Upon placement of certain construction phase financial assurance and receipt of the required notices from USFS, IDL and USACE, the Company began early works construction for the Project on October 21, 2025. The Company is currently focused on advancing the Project towards a full construction decision for the Project in 2026, including finalizing the remaining permits and securing project financing.

Since August 2025, the Company has accelerated construction readiness and contracting activities for the Project. Recent milestones include completing basic engineering and advancing detailed engineering, commencing early works construction in October 2025 and appointing Hatch as the EPCM contractor. The Company has developed procurement packages for long lead time process plant equipment. An agreement was also reached with ATCO for the design, construction and installation of a 1,010-person turnkey camp accommodation and site package. Additionally, the Company issued a request for proposal from third parties to assess the technical and economic feasibility of off-site antimony processing facilities and on December 9, 2025, the Company announced a partnership with Idaho National Labs to conduct pilot-scale testing to produce antimony trisulfide for domestic uses. The Company also commenced an exploration and geotechnical core drilling program in the fourth quarter of 2025 through the beginning of the first quarter of 2026.

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Corporate Structure

The following chart shows the intra-corporate relationships between the Corporation and its subsidiaries. Perpetua Resources Idaho, Inc. (“PRII”) has no ownership interest in the Stibnite Gold Project; rather, it is the designated operating entity of the Corporation and manages Project activities. The property holding entity, Idaho Gold Resources Company, LLC (“IGRCLLC”), is the surviving entity in a merger with Stibnite Gold Company (“SGC”), effective June 3, 2021, and is managed pursuant to an operating agreement with PRII. PRII and IGRCLLC are wholly owned by the Corporation.

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IGRCLLC holds title to the Yellow Pine, Hangar Flats and West End Deposits, all of the patented mill sites and all of the unpatented federal lode mining claims and unpatented mill sites.

Permitting and Environmental Matters

NEPA Permitting Update

Perpetua Resources is focused on the exploration and mining of the Stibnite Gold Project (the “Project”), the reclamation of prior deposits and historical tailings, and the restoration of the area to address historical activities and legacy contamination. The Project is, therefore, subject to numerous environmental regulations, including federal, state and local laws.

Significantly, we are subject to formal review under NEPA and extensive permitting requirements. In 2016, the USFS began its formal review of the Stibnite Gold Project under NEPA. The Forest Service completed scoping in 2017 and subsequently pursuant to the NEPA process, the USFS and cooperating agencies undertook extensive review of our project and proposed actions through a DEIS, released by the USFS in August 2020. In response to public and agency feedback on the DEIS, Perpetua Resources proposed modifications to the mine plan analyzed in DEIS Alternative 2 to include reduction of the project footprint, improvements in water quality, and lower water temperatures. Perpetua Resources submitted a refined proposed action to the USFS in October 2021 (the “Modified Mine Plan”).

The USFS then prepared a SDEIS to further evaluate the project refinements and compare the Company’s proposed site access via Burntlog Route to an alternative option using current roads. After nearly two years of review, the SDEIS was published on October 28, 2022 for a 75-day public comment period. The USFS identified the Modified Mine Plan as the Preferred Alternative and concluded that it would reasonably accomplish the purpose and need for consideration of approval of the Stibnite Gold Project, while giving consideration to environmental, economic and technical factors.

On September 6, 2024, the USFS published the FEIS and a DROD for the Stibnite Gold Project. The FEIS analyzes the potential environmental effects (including benefits) of the mining and reclamation activities proposed as part of the Stibnite Gold Project. The DROD outlined the USFS’s proposed decision to authorize the Modified Mine Plan and to approve a special use authorization for transmission line upgrades and installation of a new section of power transmission line with supporting infrastructure.

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On January 3, 2025, the USFS published the ROD and FEIS Errata approving the Modified Mine Plan for the Project, subject to Perpetua’s submittal of a Plan of Operations and USFS’ review and approval of the Plan of Operations. Per the requirements of the FEIS and ROD, Perpetua was required, among other things, to prepare for USFS review and approval a Plan of Operations based on the Modified Mine Plan and other plans comprising the suite of Environmental Monitoring and Management Plans. These plans were to incorporate Project updates as well as required mitigation measures, environmental protection measures, financial assurance and design features in this additional documentation. Perpetua submitted all required plans to USFS for its review.

On September 19, 2025, the USFS issued its conditional Notice to Proceed from the USFS for the Stibnite Gold Project, which stated the Project has satisfied the requirements outlined in the January 2025 ROD necessary to begin construction and that the Project may begin construction conditioned only on the Company posting of the joint construction phase financial assurance agreed to by USFS, IDL, and USACE for the Project.

Perpetua subsequently posted the agreed upon joint construction phase financial assurance for the Project, and the USFS on October 20, 2025, issued notice that the requirements necessary to start construction had been satisfied, the Plan of Operations had been approved and signed by USFS, and the Project could enter construction subject to terms and conditions specified in the notice. IDL and USACE on October 21, 2025, also issued notices confirming that the requirements necessary to begin construction under their respective approvals for the Project, including posting the agreed upon joint financial assurance, had been met and that the Company could begin construction subject to the terms and conditions identified by those agencies.

Following the USFS’ publication of the ROD and FEIS approving the Modified Mine Plan for the Project, lawsuits were filed against the USFS, USDA and other federal agencies on February 18, 2025, in the United States District Court for the District of Idaho by a number of environmental advocacy groups, including Save the South Fork Salmon, the Idaho Conservation League and other non-governmental organizations. The lawsuit alleges violations of NEPA and other federal laws in the regulatory process. Among other remedies, the claimants seek to vacate the ROD issued by USFS, the Final Biological Opinions issued by the U.S. Fish and Wildlife Service and the National Marine Fisheries Service on September 6, 2024, and October 7, 2024, respectively (together, the “Final Biological Opinions”), and other Project approvals and to enjoin any further implementation of the Project. PRII filed a motion to intervene in this lawsuit, which was granted by the district court on April 2, 2025.

On August 29, 2025, the Nez Perce Tribe filed a lawsuit against the USFS, United States Department of Agriculture and other federal agencies in the U.S. District Court for the District of Idaho challenging the USFS ROD and other approvals by the USFS and other federal agencies in connection with the Stibnite Gold Project and alleging violations of NEPA and other federal statutes, regulations, rules and requirements in the regulatory review and approval process in of the Project. Among other remedies, the Tribe seeks to vacate the USFS ROD and other Project approvals and to enjoin any further implementation of the Project. PRII filed a motion to intervene in this lawsuit, which was granted by the District Court on September 4, 2025.

The U.S. District Court on October 2, 2025 issued a general order staying all civil cases listed in the order due to the partial shutdown of the federal government over appropriations for the government. The list included the separate lawsuits filed by the Nez Perce Tribe and by the environmental advocacy groups mentioned above challenging the USFS ROD and other federal agency approvals. This stay does not affect the validity of the USFS ROD or any of the other approvals challenged in either of these lawsuits in connection with the Stibnite Gold Project, and all such approvals remain in effect. After the partial federal government shutdown ended, the District Court issued new scheduling orders in the two cases challenging the USFS ROD and other federal approvals. In the case involving the environmental advocacy groups, the scheduling order required all procedural and dispositive motions to be filed by January 20, 2026. Those pleadings have been filed by all parties. The District Court has not yet ruled on these pending motions. In the case involving the Nez Perce Tribe, all dispositive pleadings currently are required to be filed by the end of June 2026.

The two federal lawsuits referenced above remain pending. The Company believes the USFS ROD and other federal regulatory processes challenged in the two foregoing federal lawsuits were conducted thoroughly and completely by the relevant federal regulatory agencies. However, there can be no assurance that the Project approvals challenged in those two cases will be upheld upon judicial review.

On May 19, 2025, the USACE issued the CWA Section 404 permit for the Project, which included the Compensatory Mitigation Plan. USACE was a part of the review process as a cooperating agency since the Company began the federal NEPA process after filing the CWA Section 404 permit application in 2023. The CWA Section 404 permit was the last remaining federal permit needed to advance the Project towards a construction decision. On October 21, 2025, USACE issued a letter to the Company confirming that the conditions set forth in the CWA Section 404 permit necessary to begin construction, including posting of construction phase financial assurance, had been met.

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Before early works construction commenced as described in “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations – Engineering, Contracting and Construction Activities” section below, the Company entered into voluntary stipulations with the plaintiffs in the two above-mentioned federal lawsuits. Those stipulations. provide for certain restrictions on the early works construction activities for the Project until February 1, 2026, after which the stipulations will terminate on 30-days’ notice by the Company to the plaintiffs. In exchange for the Company’s commitments to these restrictions, the plaintiffs in each case agreed not to seek a preliminary injunction against development of the Project in conformance with the stipulations during the restriction period that will end when the stipulations terminate. These stipulations were filed with the U.S. District Court for the District of Idaho in the two federal lawsuits. On March 16, 2026, the Company provided notice to the plaintiffs that the stipulation restriction period will end 30 days from such notice.

Ancillary Permitting Update

With receipt of all federal permits, the Company is focused on advancing the Project towards a full construction decision, including finalizing the remaining state permits and securing project financing. Most state permits for the Project were issued as of December 31, 2025, with certain previously submitted permit applications continuing through the administrative review process as of that date. In January 2026, IDEQ issued an IPDES individual industrial wastewater discharge permit), and IDWR issued the final stream alteration permit. The IPDES industrial discharge permit is subject to an automatic stay in connection with pending administrative appeal under state law as discussed in “Item 3. Legal Proceedings” section below. IDEQ continues to review Perpetua’s application for an IPDES sanitary waste discharge permit. In July 2025, IDEQ released a draft modification to its CWA Section 401 water quality certification for public comment. The Company anticipates receiving the IPDES sanitary discharge permit by early Q2 2026 and anticipates that IDEQ will issue the final modification of its Section 401 certification in Q2 or Q3 2026. IDEQ’s CWA Section 401 certification is subject to an ongoing state administrative contested case challenge.

See “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations – Ancillary Permitting Activities” below.

Legal Proceedings

Three pending federal lawsuits and one state lawsuit involving the Company are discussed in “Item 3. Legal Proceedings” section below. Additionally, the Corporation and its subsidiaries have been parties to an ongoing legal proceeding with the Nez Perce Tribe for claimed violations of the CWA allegedly linked to historical mining activities. In August 2019, the Nez Perce Tribe filed suit against the Company in the United States District Court for the District of Idaho. The Company filed an answer generally denying liability and later, the court allowed the Company to amend and file a third-party complaint against the USFS. The Company also filed a separate CWA citizen suit against the USFS alleging that several of the point source discharges, as alleged by the Nez Perce Tribe in its complaint, were occurring on lands owned and controlled by the United States government. Pursuant to the terms of the voluntary ASAOC executed in January 2021 with the U.S. EPA and the USDA under the Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA”), the Company agreed to dismiss its pending action in the CWA case against the USFS without prejudice.

On August 8, 2023, the Company and the Nez Perce Tribe filed a final settlement agreement (the “Settlement Agreement”) to resolve the Tribe’s CWA claims. The parties jointly asked the court to approve the Settlement Agreement and dismiss the case without prejudice. The Settlement Agreement provides for total payments of $5.0 million by Perpetua over a four-year period. This includes $4.0 million of contributions by Perpetua to the Fund to be used by the Nez Perce Tribe to support water quality improvement projects in the South Fork Salmon River watershed and $1.0 million of reimbursements to the Nez Perce Tribe for legal expenses. Following a 45-day review period by the United States Justice Department and the U.S. EPA, the U.S. District Court for the District of Idaho approved the Stipulation for Dismissal and entered a Judgment on October 2, 2023, which resulted in the CWA lawsuit being dismissed without prejudice. Under the Settlement Agreement, the Company anticipates that a dismissal with prejudice will be entered after completion of Perpetua’s required payments. All required payments to date have been made timely pursuant to the terms of the Settlement Agreement. As of December 31, 2025, the current portion of the settlement was $1.0 million with the remaining $1.0 million classified as long-term.

Certain of the Company’s property interests in the Project site are also subject to existing judicial consent decrees entered into by third parties and various governmental entities with respect to contamination caused by historical mining activities on or near the Project site. These consent decrees, which impose environmental liability and remediation responsibilities on third parties, apply to certain mining claims and mill sites acquired by Perpetua from those third parties. Under the consent decrees, Perpetua is required to grant access to certain Project site areas by regulatory agencies and allow remediation activities to proceed if necessary and to preserve the integrity of previous response actions. Several of the Company’s patented claims in the Hangar Flats and Yellow Pine properties are also subject to a consent decree which requires Perpetua to cooperate with the U.S. EPA and the USFS to implement appropriate response activities.

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See “Item 1A. Risk Factors” and “Item 3. Legal Proceedings” below.

Government and Environmental Regulations

Mining operations and exploration activities are subject to extensive national, state and local laws and regulations in the United States, which govern prospecting, development, mining, production, exports, taxes, labor standards, occupational health, waste disposal, protection of the environment, mine safety, hazardous substances, disclosure requirements and other matters. The Corporation plans to obtain the licenses, permits or other authorizations currently required to conduct its exploration or development programs, and it believes it is currently in material compliance with governing mining, health, safety and environmental statutes and regulations in the United States and Idaho. Except as otherwise noted herein, we are not subject to any orders or directions with respect to the foregoing laws and regulations. For a more detailed discussion of the various government laws and regulations applicable to our operations and potential negative effects of these laws and regulations, see “Item 1A. Risk Factors” below.

Our operations are also subject to numerous environmental, health and safety laws and regulations in the jurisdictions in which we operate. These laws and regulations may require us to take precautions with respect to threatened, endangered, or otherwise protected species and their habitats as well as other natural, historical and cultural resources, perform environmental assessments or impact statements, implement siting and operational programs or best practices to minimize environmental impacts from our operations, perform investigatory and remedial obligations and obtain federal, state and local permits, licenses, or other approvals. Failure to comply with these laws and regulations may result in the imposition of significant fines or penalties. Additionally, we could experience significant opposition from third parties to our application for such permits or during the administrative agency review and appeal process after the issuance of such permits. Delays, denials of, or challenges to permits, or the imposition of costly and difficult to comply with conditions, may impair the development of our Project or curtail our planned operations. The following provides a summary of the more significant environmental, health and safety laws and regulations which our operations are subject to and for which compliance with may have a material adverse impact on our business.

National Environmental Policy Act

Our Project is subject to environmental review under NEPA. This law requires federal agencies to evaluate the environmental impact of their actions that may significantly affect the quality of the human environment; such review is a prerequisite for the granting of permits or similar authorization from federal agencies for the development of certain projects. As part of the review, the federal agencies are required to consider numerous environmental impacts, which may include potential impacts on air quality, water quality, cultural resources, wildlife, geology and aesthetics, as well as alternatives to the Project. The review process can lead to significant delays in approval of such projects and the issuance of the requisite permits which, in turn, can impact both the cost and development of operations. As a result of NEPA review, agencies may seek to deny permits or other support for a project, or condition approvals on certain modifications or mitigation actions. Additionally, authorizations under NEPA are subject to litigation, protest, or appeal, which has the potential to lead to further delays.

Pursuant to NEPA, the USFS and cooperating agencies undertook extensive review of our Project and proposed actions. As a result of this review, the USFS published the FEIS and DROD with respect to the Project on September 6, 2024 and published the ROD and FEIS Errata approving the Modified Mine Plan for the Project on January 3, 2025. Certain environmental advocacy groups on February 18, 2025 filed a lawsuit in the U.S. District Court for the District of Idaho alleging that the USFS and other federal agencies violated applicable laws and other requirements in issuing the ROD and FEIS and taking related regulatory actions. On August 29, 2025, the Nez Perce Tribe filed a separate lawsuit against the USFS, United States Department of Agriculture and other federal agencies in the U.S. District Court for the District of Idaho challenging the USFS ROD and other approvals by the USFS and other federal agencies in connection with the Project and alleging violations of NEPA and other federal statutes, regulations, rules and requirements in the regulatory review and approval process in of the Project. ongoing, and PRII has intervened in both cases. These lawsuits remain pending. See “—Permitting and Environmental Matters” above and “—Legal Update” below.

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Comprehensive Environmental Response, Compensation, and Liability Act

The site upon which our Project is located has significant legacy contamination from previous mining operations by companies not related to Perpetua. CERCLA can impose joint and several liability, without regard to fault or legality of conduct, on classes of persons who are statutorily responsible for the release of hazardous substances into the environment. These persons include current owners or operators of a site where a release has occurred. Under CERCLA, such current owners or operators may be subject to strict, joint and several liability for the entire cost of cleaning up hazardous substances and for other expenditures, such as response costs and damage to natural resources. Idaho also has environmental cleanup laws analogous to CERCLA.

Voluntary cleanup actions can be undertaken pursuant to settlement agreements under CERCLA. The Company entered into an ASAOC with the U.S. EPA and the USDA pursuant to CERCLA in 2021 to conduct a number of time critical removal actions focused on improving water quality in several areas of the site. The Company filed Removal Action Completion Reports (“RACR”) with the U.S. EPA and USDA advising the agencies that the Company believes it has completed all work required under Phase 1 of the ASAOC. The federal agencies are currently reviewing the RACR. The ASAOC includes a process under which the Company and the signatory federal agencies may evaluate whether the Company will proceed with additional response actions after the Phase 1 work has been certified by the federal agencies as complete. The scope of any such potential additional actions and their costs have not yet been determined. See Notes 6 and 9 to the Consolidated Financial Statements.

Certain of the Company’s property interests in the Project site are also subject to existing judicial consent decrees entered into by third parties and various governmental entities under CERCLA and other statutes with respect to contamination caused by historical mining activities on or near the Project site. These consent decrees, which impose environmental liability and remediation responsibilities on third parties, apply to certain mining claims and mill sites acquired by Perpetua from those third parties. Under the consent decrees, Perpetua is required to grant access to certain Project site areas by regulatory agencies and allow remediation activities to proceed if necessary and to preserve the integrity of previous response actions. Several of the Company’s patented claims in the Hangar Flats and Yellow Pine properties are also subject to a consent decree which requires Perpetua to cooperate with the U.S. EPA and the USFS to implement appropriate response activities.

Protection of Species and Habitat

The Company’s operations are subject to several environmental regulations and guidelines regarding various protected species and their habitats and include the federal Endangered Species Act, the Migratory Bird Treaty Act and the Bald and Golden Eagle Protection Act, alongside similar state laws. These laws impose significant civil and criminal penalties for violations, including injunctions limiting or otherwise prohibiting operations in certain areas where protected species or their habitats are located. The imposition of such restrictions, such as seasonal limitations, may result in additional costs and delays and could impact the feasibility of our Project.

Clean Water Act

The CWA and other similar federal and state laws and regulations require the Company to obtain permits for water discharges or take mitigation actions with respect to the loss of wetlands. Additionally, such regulations require us to implement a variety of best management practices to ensure that water quality is protected and possible impacts of our operations on water quality are minimized. The CWA and analogous laws and regulations provide for administrative, civil and criminal penalties for unauthorized discharges of pollutants in reportable quantities and may impose substantial potential liability for the costs of addressing such discharges. The Nez Perce Tribe in 2019 filed a lawsuit against the Company in the U.S. District Court for the District of Idaho alleging violations of the CWA due to, among other things, exceedances of applicable water quality standards in certain water bodies in the vicinity of the Project site. The Company entered into a settlement of this litigation with the Nez Perce Tribe in 2023. See “Item 3. Legal Proceedings” below.

Clean Air Act

The Clean Air Act and other similar laws and regulations require the Company to obtain permits before construction can commence on a new source of potentially significant air emissions. Additionally, the U.S. EPA establishes and periodically reviews emissions standards that require the maximum degree of reduction in emissions of hazardous air pollutants from major sources, and we are required to comply with such emissions standards where applicable. The U.S. EPA and state agencies such as the Idaho Department of Environmental Quality have the ability to issue citations and orders and assess penalties for violations of permits or other applicable regulatory requirements.

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Mine and Safety Health Administration

Mining operations are regulated by MSHA which carries out the provisions of the Federal Mine Safety and Health Act of 1977, as amended by the Mine Improvement and New Emergency Response Act of 2006. MSHA enforces the health and safety rules for all U.S mines and conducts mine inspections regarding compliance with applicable laws and regulations. MSHA has the ability to issue citations and orders and assess penalties for health and safety violations.

District Exploration

During the fourth quarter of 2025 a short exploration and geotechnical core drilling program was initiated and continued through the beginning of the first quarter of 2026. A total of 4 exploration and 15 geotechnical holes were completed with a cumulative 9,136 feet completed. Logging and sampling of the drill holes were in progress at the effective date of this Annual Report.

Employees

At December 31, 2025, the Corporation had 47 full time employees, 1 part time employee and 1 temporary employee. 46 employees were directly related to the mineral development activities of the Stibnite Gold Project and the remaining 3 employees were focused on executive management, investor relations and administrative support of the Corporation. A total of 34 employees were employed in Idaho, with many of the Perpetua Resources team working remotely. The Corporation also contracts out certain activities to contractors with specific skills to assist with various aspects of the Project.

Royalties and Option Agreements

Option Agreements

On May 3, 2011, a predecessor to Perpetua entered into an option to purchase (“OTP”) to purchase 27 patented lode claims totaling approximately 485 acres from the J.J. Oberbillig Estate (the “Cinnabar Option Claims”). This agreement was modified in an Amended and Restated Real Property Purchase Agreement effective December 1, 2016 (the “amended agreement”). The amended agreement also includes an assignment of the right of first refusal to purchase the surface rights associated with portions of certain patented mill site claims that J.J. Oberbillig Estate sold to Hecla under a Real Estate Purchase and Sale Agreement effective December 30, 2002. The OTP has annual payments and can be extended up to 10 years after the original term of the agreement expires, through December 1, 2037, for additional consideration.

On December 10, 2019, a Perpetua Resources subsidiary entered into an option agreement to purchase 3.74 acres from private interest for an electrical switching station site which has a biannual payment of $2,500 through 2033.

Royalty Agreement

Effective May 9, 2013, Perpetua Resources and its subsidiaries granted a 1.7% NSR royalty on future gold production from the Project properties to a wholly owned subsidiary of Franco-Nevada Corporation (such subsidiary, “FNIC”), subject to adjustment based on final permitted capacity. The royalty does not apply to production of antimony and silver.

On March 21, 2024, Perpetua Resources entered into a royalty agreement with FNIC pursuant to which Perpetua Resources, through its subsidiaries, sold to FNIC a royalty on the future payable silver production from the Project in exchange for a cash payment of $8.5 million. The silver royalty agreement applies to the same properties as the gold royalty.

For a more detailed description of the terms of the option and royalty agreements, see “