Capstone Copper Sold Cozamin Four Days Before a Royalty Claimant Disclosed a Prosecutor's Demand

On September 25, 2026, Royalties Inc. issued a release saying that the state prosecutor's office in Zacatecas had formally served Capstone Copper's Mexican subsidiary with a demand to produce mine records for a criminal investigation. Capstone Copper Corp. (TSX: CS) has published nothing about it.

Royalties Inc. is not a neutral narrator. It says it owns 88 per cent of Minera Portree de Zacatecas, the company claiming a royalty over part of the Cozamin mine, and it is the party pressing the case against Capstone. Every fact below that comes from its releases is its account, not a court's and not Capstone's. What can be checked independently is the calendar, and the calendar is where this story is.

January 2002: a two per cent royalty is registered over five claims

Royalties Inc. states that a 2 per cent net smelter return royalty over five mining concessions, the Portree claims, was created on January 11, 2002 and registered in Mexico's Public Mining Registry as No. 74/2002 on April 5, 2002. A net smelter return royalty is a percentage of revenue from metal sold, paid before the mine's costs, so it survives changes of owner and does not depend on whether the mine is profitable.

The claimant estimates the royalty covers about 33 per cent of Cozamin's current production value. That is its estimate, from its own release of May 22, 2026, and it has not been reproduced from a Capstone filing.

2010: Capstone begins mining over the claims

Capstone started mining at Cozamin in 2010, per the same Royalties Inc. account. The mine produces copper with silver, zinc and lead by-products near the city of Zacatecas.

August 2019: an assignment two courts have since voided, according to the claimant

The dispute turns on a 2019 transfer of the royalty. Royalties Inc. says the assignment was made without the consent of the royalty's owner, and that Mexican courts have since declared it "legally non-existent", finding the royalty never left Minera Portree's ownership. It dates Capstone's liability for unpaid royalties from August 9, 2019.

Two named decisions support that account in the claimant's telling: a first-instance judgment on June 16, 2025 and a confirmation on November 4, 2025 by the Civil Chamber of the Zacatecas Superior Court of Justice. Neither judgment has been read for comparison against this account, and Capstone has published no statement responding to either.

2022: the dispute acquires a criminal file number

A civil argument about who owns a royalty became a criminal file in 2022. Royalties Inc. cites a criminal investigation under the reference CUI: 9367-UEI-FRAU-2022, opened on a complaint by Minera Portree alleging fraudulent administration and fraud, against Raúl González Anaya. The accused there is an individual named as an assignee of the royalty, not Capstone.

That distinction carries most of the weight in this story, so it is worth setting out the four things a Mexican criminal file can contain, because they are routinely collapsed into one another:

On the claimant's own description, the Cozamin matter is at the second row against Capstone's subsidiary and the third row against an individual. No Capstone entity, officer or director has been reported as charged by anyone, and the September 25, 2026 release does not say otherwise.

November 25, 2025: an amparo is filed, and it is still undecided

Capstone filed an amparo on November 25, 2025, per Royalties Inc. An amparo is a constitutional challenge in Mexican federal court; here it is described as seeking to recharacterise the finding of non-existence as a lesser defect. As of the claimant's May 22, 2026 release the federal Collegiate Tribunal had not ruled, and the claimant said the Attorney General's office had recommended the amparo be denied.

Pending means pending. A recommendation is not a decision, and the company that filed the amparo has not published its own account of its prospects.

September 7, 2026: a prosecutor's office asks the mine for its production records

This is the document at the centre of the September 25 release. Royalties Inc. describes a formal service document, an ACUSE, dated September 7, 2026, requiring Capstone Gold's legal representative to produce fourteen categories of material, including underground mine documents, maps, three-dimensional block models, payment records and wire transfers. It quotes a warning that failure to comply, or the submission of false information, would trigger enforcement measures under Article 104 of Mexico's National Code of Criminal Procedure.

Production records, maps and block models are the raw material for calculating how much metal came out of specific concessions. A claimant with a percentage royalty over five of them needs exactly that to size its claim. The demand, if it was served as described, is an evidence-gathering step in a valuation fight as much as a criminal one.

Capstone has not confirmed receiving it. The service of process is the claimant's assertion; it is not independently established here.

September 21, 2026: Capstone agrees to sell Cozamin, and the release says nothing about any of this

Fourteen days after the date on that document, Capstone announced the sale of Cozamin to Luca Mining Corp. The company's own release of September 21, 2026 sets out the consideration in US dollars: US$275 million cash at closing on a cash-free, debt-free basis with a lock-box date of October 31, 2026; US$15 million in Luca shares at closing; US$35 million deferred to the first anniversary, in cash or Luca shares at Luca's option; and up to US$60 million contingent on annual London Metal Exchange copper prices from 2027 to 2029. Up to US$385 million in total, about C$544 million at the Bank of Canada's daily average rate of 1.4136 for September 24, 2026.

Closing is expected in the fourth quarter of 2026, subject to customary conditions, stock exchange approvals and clearance from Mexico's national antitrust commission. The release states the transaction is not subject to shareholder approval or any financing condition. Cashel Meagher, president and chief executive officer, is quoted saying net proceeds will strengthen the balance sheet and allow capital to be redeployed into higher-return growth projects.

The words royalty, net smelter return, Portree, litigation, court, amparo, criminal, indemnity and material adverse change do not appear anywhere in that release. Nor does Royalties Inc. The document sets out conditions and a forward-looking risk recital, and neither mentions the dispute.

That absence is not by itself a failure of disclosure. A release announcing a transaction is not a continuous-disclosure document, and Capstone's assessment of materiality is properly made against its own consolidated position, not against the asset being sold. But it is the reason the sequence is worth laying out: a company disclosed a sale of the asset, and a claimant disclosed a prosecutor's demand over the same asset, four days apart, and only one of the two documents acknowledges that both things exist.

September 25, 2026: the counterparty discloses it, and the market does not care

Capstone closed at C$14.47 on September 25, 2026, down 0.69 per cent, on 0.27 times its 30-day average volume, per market data read after the close and delayed fifteen minutes. That is a quiet Friday on light trading, at a market value of about C$11.1 billion.

The indifference is arithmetically defensible at the parent level. Royalties Inc.'s own estimate of its total claim is US$50 million: US$15 million of arrears from 2019 to 2025 with 10 per cent cumulative interest, US$15 million of royalties from 2026 to 2030, and US$20 million of value after 2030. About C$70.7 million, or 0.64 per cent of Capstone's market value. A company of that size can absorb it without a line in a headline.

Against the transaction, the same figure reads differently. US$50 million is 18.2 per cent of the US$275 million of cash at closing and 13 per cent of the maximum US$385 million. The buyer, Luca Mining, is a far smaller company acquiring an asset with a contested 2 per cent royalty over concessions the claimant says cover about a third of production value, with a federal amparo undecided and a prosecutor's evidence demand outstanding. Whether that risk was priced into the consideration, allocated by indemnity, or left with the asset is not in the public release.

Retail discussion of Capstone this week ran to governance rather than operations, and the sharpest of it was not evidence of anything. The document demand was reported by the adverse party. The rulings behind it have not been read. The one thing not in dispute is the calendar.

What is filed and what is not

Three documents would settle most of this, and none of them is public. The Collegiate Tribunal's decision on the amparo would determine whether the 2019 assignment stands. The share purchase agreement with Luca would show how the royalty was allocated between seller and buyer. Capstone's next continuous-disclosure filing would show what the company itself says about a contingency a counterparty has now put on the wire twice in four months.

SEDAR+ was not readable when this was written, so nothing here is checked against Capstone's interim filings; the sale terms are from the company's own release and the dispute history is from the claimant's. Until one of those three documents surfaces, the strongest statement the public disclosure supports is narrow: an asset was sold while a claim over part of its revenue was live, and the release announcing the sale did not say so.

Transparency note

Transparency note. This is an independent due-diligence analysis and editorial opinion piece produced by The Maple Markets editorial desk. It is not sponsored, promoted or commissioned, and no compensation of any kind has been received from Capstone Copper Corp. (TSX: CS), Royalties Inc. (CSE: RI), Luca Mining Corp. (TSXV: LUCA) or any party acting on their behalf. The analysis is based on public disclosure available as of the publish date; every figure is attributed to its primary source. The Maple Markets and its authors may hold positions in securities mentioned; nothing here is a recommendation to buy, sell or hold any security, and readers should not treat it as investment advice. Past disclosure does not guarantee future results. Policies: Editorial Standards · Financial Disclaimer.