Rio Tinto plc and Rio Tinto Limited filed a Form 6-K with the U.S. Securities and Exchange Commission on 2 November 2026, covering stock exchange announcements and media releases issued during the month of October 2026.

Key Highlights

  • Kangwinan bauxite investment: According to the filing, a media release dated 23 October 2026 announced Rio Tinto's plan to invest $1.9 billion to develop the Kangwinan bauxite project in Western Cape York, Queensland.
  • Argentina lithium projects: A media release dated 29 October 2026 disclosed the opening of $1.4 billion lithium projects in Argentina.
  • Bell Bay Aluminium agreement: A media release dated 1 October 2026 reported that Rio Tinto, the Tasmanian Government, and the Commonwealth Government secured the future of Bell Bay Aluminium until 2031.
  • Share issuance and voting rights: Stock exchange announcements dated 1 October 2026 covered total voting rights and issued capital, as well as an issue of shares.
  • PDMR/KMP shareholding disclosures: Shareholding announcements for persons discharging managerial responsibility and key management personnel were filed on 2 October, 8 October, and 22 October 2026.
  • Substantial holder notices: A notice of initial substantial holder (Form 603) was announced on 7 October 2026, and a notice of ceasing to be a substantial holder (Form 605) was announced on 8 October 2026.

Rio Tinto's October 2026 Disclosures: Bauxite, Lithium, and Capital Events

The Form 6-K, filed by both Rio Tinto plc (commission file number 001-10533) and Rio Tinto Limited (commission file number 001-34121) and signed on 2 November 2026, bundles thirteen exhibits covering corporate, capital markets, and operational announcements made during October 2026. The filing does not contain detailed financial statements; rather, it incorporates by reference the underlying stock exchange announcements and media releases as exhibits numbered 99.1 through 99.13.

Among the most significant items disclosed, according to the filing, are two capital investment announcements. A media release dated 23 October 2026 stated that Rio Tinto intends to invest $1.9 billion to develop the Kangwinan bauxite project in Western Cape York, Queensland. Separately, a media release dated 29 October 2026 described the opening of $1.4 billion lithium projects in Argentina. The filing also references a 1 October 2026 media release announcing that Rio Tinto, the Tasmanian Government, and the Commonwealth Government "secure the future of Bell Bay Aluminium until 2031," using the language from the exhibit title as disclosed.

On the capital and governance side, the filing attaches announcements covering issued capital and total voting rights, an issue of shares, three separate PDMR/KMP shareholding disclosures, and two Appendix 3G notifications for unquoted equity securities alongside an Appendix 3H cessation-of-securities notification. Substantial holder notices were filed on both 7 October and 8 October 2026. The filing was signed by Matthew Whyte as Company Secretary of Rio Tinto plc and Tim Paine as Company Secretary of Rio Tinto Limited, each on 2 November 2026. The filing indicates Rio Tinto files annual reports under Form 20-F.

What Was Disclosed

Rio Tinto filed a Form 6-K covering the month of October 2026, attaching thirteen exhibits that include media releases on a $1.9 billion bauxite project and $1.4 billion lithium projects, share and voting rights announcements, substantial holder notices, and multiple PDMR/KMP shareholding disclosures.