The largest group claim ever tried in England: ~620,000 Brazilian claimants sued BHP’s parent companies over the 2015 Fundão (Mariana) tailings-dam collapse. In November 2025, the High Court found BHP liable under Brazilian law. Appeals against liability have been refused, and a quantum trial on claims put at up to £36B is listed for late 2027 into 2028.
LATEST DEVELOPMENT · MAY 6, 2026
On 6 May 2026, the Court of Appeal ([2026] EWCA Civ 502) refused BHP permission to appeal the liability judgment on all substantive grounds, leaving only an expedited costs-interest appeal (listed for around October 2026). The Stage 2 quantum trial is listed for the second half of 2027 into 2028.
BACKGROUND
On 5 November 2015, the Fundão tailings dam at the Samarco iron-ore mine, a 50/50 joint venture of BHP and Vale, collapsed, killing 19 people and sending mine waste down the Rio Doce to the Atlantic in what is often described as Brazil’s worst environmental disaster. Group proceedings issued in England in 2018 against the UK and Australian BHP parents were struck out as an abuse of process in 2020, reinstated by the Court of Appeal in 2022 and, after the Supreme Court refused BHP permission in 2023, went to a Stage 1 liability trial before Mrs Justice O’Farrell between October 2024 and March 2025. Shortly after the trial opened, BHP, Vale and Samarco signed a R$170B (≈US$30B) settlement with the Brazilian authorities, which BHP argued answered much of the English claim. BHP’s contribution claim against Vale settled separately on a 50/50 basis.
On 14 November 2025, in a 1,129-paragraph judgment ([2025] EWHC 3001 (TCC)), the court held BHP liable under Brazilian law, strictly, as a “polluter” under the Environmental Law, and on a fault basis under the Civil Code, and largely rejected its limitation defenses. O’Farrell J refused permission to appeal in January 2026 save on a single costs-interest ground, and on 6 May 2026 the Court of Appeal refused permission on every substantive ground, holding none reasonably arguable, while expediting the surviving costs appeal to around October 2026. The Stage 2 trial on causation and quantum, against claims the claimants value at up to £36B, is listed for the second half of 2027 into 2028, with individual entitlements to follow.
TIMELINE
-
MAY 6, 2026APPEALCourt of Appeal refuses permission on all substantive grounds[2026] EWCA Civ 502 (Lewison and Fraser LJJ): no liability or limitation ground reasonably arguable. The costs-interest appeal expedited for around October 2026, with the Stage 2 quantum trial listed for late 2027 into 2028.
-
JAN 19, 2026PROCEDURALTrial judge refuses permission to appealO’Farrell J’s consequentials judgment ([2026] EWHC 73 (TCC)) refused permission except on interest on costs. Claimants’ costs to that point were recited at about £189M net.
-
NOV 14, 2025JUDGMENTBHP found liable[2025] EWHC 3001 (TCC): BHP held strictly liable as a polluter under Brazilian environmental law and liable in fault under the Civil Code. Limitation defenses largely rejected.
-
OCT 7, 2024HEARINGStage 1 liability trial opensThe trial ran to 13 March 2025 (about 50 hearing days) before Mrs Justice O’Farrell. Shortly after it opened, BHP, Vale and Samarco signed a R$170B settlement with Brazilian authorities.
-
JUL 8, 2022APPEALCourt of Appeal revives the claims[2022] EWCA Civ 951 reinstated the group action. The Supreme Court refused BHP permission to appeal in 2023.
-
NOV 9, 2020JUDGMENTClaims struck outTurner J struck out the claims as an abuse of process in light of parallel Brazilian proceedings and remediation schemes.
-
NOV 2018FILINGGroup action issued in EnglandClaims were brought against the UK and Australian BHP parent companies on behalf of a group that grew to roughly 620,000 Brazilian claimants.
-
NOV 5, 2015OTHERFundão tailings dam collapsesThe dam at the Samarco mine, a 50/50 BHP–Vale joint venture, failed, killing 19 people and polluting the Rio Doce for hundreds of kilometres to the Atlantic.