HSBC Holdings has agreed to pay $30 million (R415m) to settle litigation by investors who accused 11 big banks of rigging the roughly $9 trillion government agency bond market from 2009 to 2015.
The settlement with the British bank was made public late Wednesday night in the federal court in Manhattan and requires approval by US District Judge Edgardo Ramos.
HSBC is the third bank to settle, after Deutsche Bank and Bank of America agreed in August 2017 to pay a respective $48.5m and $17m and co-operate with the plaintiffs.
Investors led by two Alaska government entities and the Iron Workers Pension Plan of Western Pennsylvania accused banks of colluding to manipulate prices of US dollar-denominated supranational, sub-sovereign and agency bonds.
They said the banks used chatrooms and other means to share price data and coordinate trading, effectively functioning as a single "super-desk," to reduce competition and boost profit on "virtually every trade" at customers' expense.
"Rare is an antitrust case like this one, where a large volume of 'smoking gun' evidence exists at the pleading stage," they said in an amended complaint filed on November 13.
HSBC denied liability but settled to avoid more litigation that could prove "extraordinarily expensive and time-consuming," according to its settlement agreement.
It also agreed to co-operate with the plaintiffs, including by providing evidence such as electronic chats among the banks.
A spokesperson, Rob Sherman, declined additional comment on Thursday.
The remaining defendants include Barclays, BNP Paribas, Citigroup, Credit Agricole, Credit Suisse Group, Nomura Holdings, Royal Bank of Canada and Toronto-Dominion Bank.
Ramos has yet to rule on their requests to dismiss the amended complaint.