19 people died, villages were destroyed and about 700,000 people lost their homes in the 2015 disaster. More than 600,000 claimants seek compensation, worth about £36bn.
The trial is split into two stages. In November, the claimants, represented by Pogust Goodhead, secured a victory in the stage 1 trial ([2025] EWHC 3001 (TCC)), when the High Court found the mining company strictly liable as ‘polluters’ for the damage caused by the collapse.
In Município De Mariana v BHP Group (UK) and another [2026] EWHC 73 (TCC), the claimants sought £113.5m costs for the stage 1 trial, plus pre-judgment interest. They calculated their total costs at that point as £189m.
The defendants contested this sum as ‘shockingly excessive’ compared to their own costs of £125m.
Delivering her judgment this week, Mrs Justice O’Farrell held BHP should pay 90% of the claimants’ costs for the first stage. However, she slashed the sum to £43m.
O’Farrell J noted there had been no costs budgeting for the stage 1 trial and the statement of costs contained ‘a very high-level overview’ of the categories and amounts. It included £14m for counsel fees ‘identified as lump sums for each individual’, she said, as well as £44m for a walk-in centre and call centre fee earners, £73m for UK fee earners and £73m for Brazil fee earners. While the ‘rates, hours and total sums are tabulated for each fee earner’ between 2018 and 2025, there was ‘no link to the tasks carried out by those individuals or the dates on which work was carried out’.
O’Farrell J said the litigation was ‘very complex’ with ‘significant challenges’ given many of the claimants live in rural Brazil. Nevertheless, the costs were ‘extraordinarily high and the level of detail provided very limited’.
She decided the walk-in centre and call centre costs were not recoverable at this stage, took £7m off the disbursements and, ‘adopting a cautious approach’ of 60% rather than 90% of the remainder, arrived at the final £43m sum.
