Platinum Group Metals

The following assumptions were used in valuing share purchase options granted during the period ended May 31, 2026 and the year ended August 31, 2025: Period ended May 31, 2026 August 31, 2025 Risk-free interest rate 2.67% 2.72% Expected life of options 3.5 years 4.1 years Annualized volatility 1 73% 77% Forfeiture rate 0.5% 0.4% Dividend rate 0.0% 0.0% 1 The Company uses its historical volatility as the basis for the expected volatility assumption in the Black Scholes option pricing model.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

Factors that could cause actual results or events to differ materially from current expectations include, among other things: future sales of Common Shares under the 2026 ATM; the Company's additional financing requirements; the effect of future debt financing on the Company and its financial condition; 3 PLATINUM GROUP METALS LTD.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

At current metal prices, increased revenue per tonne from mining the T-Zone would more than offset higher mining costs, and may allow for a lower capex, staged development approach as described above.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

On November 6, 2017, the Company, along with JOGMEC and Mnombo closed a strategic transaction to sell to Impala Platinum Holdings Ltd.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

Notes to the Unaudited Interim Condensed Consolidated Financial Statements For the nine-month period ended May 31, 2026 ( in thousands of United States Dollars unless otherwise specified except share and per share data ) (c) In May 2018, Deepkloof made a strategic investment in the Company by way of participation in a public offering and a private placement.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

(" Platinum Group ", the " Company " or " PTM ") is dated as of July 15, 2026, and focuses on the Company's financial condition, cash flows and results of operations as at and for the three-month and nine-month periods ended May 31, 2026.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

The words "expects", "anticipate", "estimate", "forecast", "may", "could", "might", "will", "would", "should", "intend", "believe", "target", "budget", "plan", "strategy", "goals", "objectives", "projection" or the negative of any of these words and similar expressions are intended to identify Forward-Looking Statements, although these words may not be present in all Forward-Looking Statements.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

The Company's business is currently focused on the engineering and development of the Waterberg Project, which hosts a PGE and base metal bearing deposit discovered in 2011 by the Company as a result of a regional exploration initiative targeting a previously unknown extension to the Northern Limb of the Bushveld Igneous Complex in South Africa.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

to fund their pro rata portion of the funding obligations for the Waterberg Project; impacts of current and future tariffs and duties; risks relating to relations between South Africa and the United States; revenue, cash flow and cost estimates and assumptions; the ability of state electricity utility ESKOM Holdings SOC Limited (" ESKOM ") to supply sufficient power to the Waterberg Project; future events or future performance; development of next generation battery technology by the Company's battery technology joint venture (described below); potential benefits of Lion Battery Technologies Inc.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

Forward-Looking Statements are subject to a number of risks and uncertainties that may cause the actual events or results to differ materially from those discussed in the Forward-Looking Statements, and even if events or results discussed in the Forward-Looking Statements are realized or substantially realized, there can be no assurance that they will have the expected consequences to, or effects on, the Company.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

shareholders; litigation or other legal or administrative proceedings brought against or relating to the Company, including the review application to set aside a decision by the Minister of the DFFE to refuse condonation for the late filing of the appeal by individuals from a community group against the grant of an EA for the Waterberg Project and an application brought by a group within two local communities, claiming they represent those communities, seeking to declare invalid the grant of a mining right to Waterberg JV Co.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

by the DMPR; information systems and cyber security risks; actual or alleged breaches of governance processes or instances of fraud, bribery or corruption; exploration, development and mining risks and the inherently dangerous nature of the mining industry, including environmental hazards, industrial accidents, unusual or unexpected formations, safety stoppages (whether voluntary or regulatory), pressures, mine collapses, cave ins or flooding and the risk of inadequate insurance or inability to obtain insurance to cover these risks and other risks and uncertainties; 4 PLATINUM GROUP METALS LTD.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026

Dollar, the South African Rand and the Canadian Dollar; volatility in metals prices; the uncertainty of alternative funding sources for Waterberg JV Co.

SEC original ↗Platinum Group Metals — Earnings release (6-K exhibit)EX-99Jul 15, 2026