The mudflow created by the dam rupture ultimately travelled 600 kilometres to the ocean, creating a toxic brown plume visible from space. 700 people lost their homes, 8,500 fishermen lost their livelihoods, and 400,000 people lost access to fresh water. It is the worst environmental disaster in Brazil’s history.

The Germano mine is operated by Samarco Mineração SA, a joint venture of BHP and Vale SA. BHP is an Anglo-Australian owned multinational and the world's largest diversified mining and mineral resources company.

In the period that followed the dam collapse, BHP’s stock price plunged across all markets, falling 22% in Sydney and 23% in London and Johannesburg between 5 November 2015 and 30 November 2015. The class action will seek to recover losses to BHP Ltd and BHP Plc shareholders throughout this period, during which BHP’s combined market capitalisation fell by more than $25 billion.

The BHP Class Action alleges that BHP Group Ltd:

1. contravened its continuous disclosure obligations between 8 August 2012 and 9 November 2015 (inclusive) (Claim Period) by failing to properly inform the Australian Securities Exchange (ASX) of BHP’s knowledge of the Fundão dam (located in the Germano mine in Minas Gerais, Brazil, operated by Samarco Mineração SA, a non-operated joint venture between BHP Billiton Brasil Ltda and Vale SA in Brazil) being at risk of failure, and knowledge that if the dam failed serious adverse human, environmental, and financial consequences would likely result;
2. (engaged in misleading or deceptive conduct by representing to the ASX (by publishing in its annual reports between FY11 – FY15) that:
   1. the primary consideration in every aspect of BHP’s business was the safety of its people and the safety and sustainability of the environment and the communities in which it, and its subsidiaries, carried on business; and
   2. BHP had effective systems and processes in place to identify and effectively manage risks to the safety of its people and the safety and sustainability of the environment and the communities in which it, and its subsidiaries, carried on business, including the Samarco mining operation.

The BHP Class Action alleges that investors who acquired BHP Ltd or BHP Plc shares in the Claim Period are entitled to compensation for loss and damage as they paid more for those shares than they would have paid as a consequence of BHP’s conduct. The BHP class action also alleges that some Group Members would not have purchased BHP Ltd or BHP Plc shares if BHP had complied with its obligations.

A class action against BHP in the United States on behalf of investors that acquired New York Stock Exchange (NYSE) listed American Depository Shares settled on 9 August 2018. The US proceeding did not (and cannot) recover losses suffered in respect of shares traded on the ASX, LSE or JSE. Investors that participated in the US proceeding, who also acquired BHP Ltd and/or BHP Plc shares may also participate in this class action.