What Is an NI 43-101 Technical Report?

NI 43-101 is the Canadian rule that governs how mining companies disclose scientific and technical information about their projects. Its full name is National Instrument 43-101, Standards of Disclosure for Mineral Projects. It sets who can sign off on the numbers, what a technical report must contain, and when one has to be filed.

Almost every resource estimate, drill program and mine study published by a Canadian-listed junior traces back to this rule. When a company says how much metal it has, this rule decides what it may say. It also decides how the claim must be backed up.

What is NI 43-101 and who does it apply to?

NI 43-101 is a rule made by the Canadian Securities Administrators, the umbrella group for the provincial and territorial securities regulators. It covers technical information about mineral projects that is made public in Canada, filed or not. That includes news releases, websites and investor presentations as well as formal filings.

The core requirement is simple. Under section 2.1 of the rule, technical disclosure about a company's important properties must come from a qualified person. That person must prepare it or approve it. A "mineral project" is broad: it includes exploration, development and production, and even royalty interests.

What is a qualified person?

A qualified person, or QP, is the professional who takes responsibility for a company's technical numbers. Under NI 43-101, a QP must be an engineer or geoscientist. They need at least five years of experience in exploration, mine building, mine operation or project assessment. They also need experience relevant to the project and must be in good standing with a professional association.

Some reports need an independent QP, meaning there's no circumstance that a reasonable person would think could interfere with their judgment. Independence is required in key cases. These include a company's first listing as a reporting issuer and its first disclosure of resources, reserves or a preliminary economic assessment. A change of 100% or more in total resources or reserves also needs one. At least one QP must also visit the property before a technical report is filed.

When does a company have to file a technical report?

A company has to file a technical report for each material property when it becomes a reporting issuer in Canada. After that, certain disclosures trigger a new report. For juniors, the usual trigger is a news release. If it gives resources, reserves or a preliminary economic assessment for the first time, and that's a material change, a report is needed.

The report is then due within 45 days. When it's filed, the company must put out another release explaining any material differences. Regulators have also said, in CSA Staff Notice 43-307, that results shown in presentations, fact sheets or on a website can trigger it too.

What does a technical report contain?

A technical report follows a set structure laid out in Form 43-101F1, with 27 numbered items. The form says the intended audience is the investing public and their advisers, most of whom won't be mining experts. Items you'll find in most reports include:

• Property description and location, and the company's rights to it.
• Geological setting and mineralization.
• Exploration and drilling, with sample preparation, analyses and security.
• Data verification, where the QP explains how the data was checked.
• Mineral processing and metallurgical testing.
• Mineral resource estimates, and reserve estimates where they exist.
• Recommendations for the next stage of work, often with a budget.

Advanced properties must cover more. These are properties with reserves, or with resources backed by an economic study. Their reports add mining methods, costs and an economic analysis. For juniors, the recommendations section is worth reading closely, because it shows what the QP thinks the next step should cost.

What are the CIM resource and reserve categories?

NI 43-101 uses the definitions set by the Canadian Institute of Mining, Metallurgy and Petroleum (CIM). The CIM Definition Standards, adopted in May 2014, split mineral resources into inferred, indicated and measured categories, in order of increasing geological confidence. A mineral reserve is the economically mineable part of a measured or indicated resource.

The rule limits what companies can do with the least certain category. Inferred resources can't be added to the other categories, and they can't be used in the economic analysis of a pre-feasibility or feasibility study. A preliminary economic assessment may include them, but only with a prominent warning that they're too speculative geologically to be counted as reserves. Our guide How to Read a Rare Earth Resource Estimate walks through each category and the study levels.

What can't a company say under NI 43-101?

NI 43-101 bars several kinds of statements that could mislead investors. A company can't state the quantity or grade of a deposit that hasn't been classified as a resource or reserve. It can't publish an economic analysis that relies on inferred resources, outside a properly cautioned preliminary economic assessment. And a metal-equivalent grade has to come with the grade of each metal behind it.

Older "historical estimates" from before a company's time can be mentioned, but only with set warnings. One warning must say a QP hasn't done enough work to treat them as current resources or reserves. Our guide How to Read Drill Results covers the rules for reporting drill holes.

Can PhotonAssay results be used in an NI 43-101 report?

Yes, if the qualified person is satisfied they're reliable. NI 43-101 doesn't list approved assay methods. Its companion policy says the methods for collecting, analysing and verifying data "are the responsibility of the qualified person." So no rule approves or bans PhotonAssay by name. The QP has to stand behind it.

PhotonAssay measures gold, and at some labs silver and copper, using high-energy X-rays. It was developed by CSIRO, Australia's national science agency, and is sold by Chrysos Corporation. Fire assay melts a small sample of about 30 to 50 grams. PhotonAssay instead scans a whole jar of crushed rock, typically 400 to 650 grams, without destroying it, in about two minutes. ALS, Intertek, SGS and MSALABS all run units, and Chrysos reported 43 deployed worldwide in its February 2026 results.

What a report has to show about any assay method is set out in Form 43-101F1. Item 11 asks for the lab's name and location, whether it's certified by a standards association, a summary of the quality control results and the QP's opinion on whether the procedures are adequate. Item 12 covers how the QP checked the data. For PhotonAssay, three things are worth looking for:

• Lab accreditation. It's granted lab by lab. MSALABS in Val-d'Or, Quebec, holds ISO/IEC 17025 accreditation for its photon assay gold method, for example. A 2025 New Found Gold technical report notes that ALS's Thunder Bay lab was not accredited for it at the time.
• Check assays. In that New Found Gold report, 249 photon assay samples were re-tested by screen fire assay. The QP concluded that fire assay, photon assay and screen fire assay were all suitable for the project.
• Interference. ALS warns that low levels of uranium or thorium, and moderate amounts of barium, interfere with the gold reading.

PhotonAssay is a gold, silver and copper method. We found no sign of it being used to measure rare earths, so rare earth grades in technical reports come from other lab methods.

Where can you find a company's technical report?

Technical reports are filed on SEDAR+, the electronic filing system used by Canadian securities regulators. Search for the company's profile and look for documents filed as a technical report. Many companies also post the report on their own website, but the filed version is the official one. The report names its QPs and its effective date. Each QP also signs a certificate, usually at the back, giving their qualifications and the date they visited the property.

Is NI 43-101 changing?

A replacement has been proposed but hasn't taken effect. In June 2025 the Canadian Securities Administrators published a proposal to repeal and replace NI 43-101 with a simpler rule and form. Comments closed on October 10, 2025. Among other changes, it would replace the preliminary economic assessment with a "scoping study" based on a new CIM definition.

Until a final rule is adopted, the current NI 43-101 still applies, and reports you read today will use its terms. Companies on our rare earth, gold and copper lists all report under it.

Sources

• National Instrument 43-101, Standards of Disclosure for Mineral Projects (consolidated to June 9, 2023), BC Securities Commission copy
• Form 43-101F1, Technical Report
• CIM Definition Standards for Mineral Resources and Mineral Reserves (2014)
• CSA Staff Notice 43-307, Mining Technical Reports: Preliminary Economic Assessments (2012)
• Canadian Securities Administrators, Notice and Request for Comment on a new NI 43-101 (June 12, 2025)

Related guides

• How to Read Drill ResultsGrams per tonne, core length versus true width, and the details a drill-result release should include.
• What Are Flow-Through Shares?How Canadian junior miners fund exploration, and how the 15% and 30% exploration tax credits work.
• TSX vs TSX Venture vs CSECanada's three stock exchanges for mining companies: who lists where, the listing rules, and what changes for investors.
• What Are Rare Earth Elements?Seventeen metals, most of them not rare at all. What they are and what they are used for.