The new accusations, leveled by several pension funds and wealthy individual investors, are contained in an expanded class-action suit originally filed in July 2015 — and include an unusual twist: Some of the evidence came from confidential informants and one of the banks sued in the earlier action.
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The funds, representing retirees and public workers, also claim the banks conspired to rig the secondary Treasury markets beginning in the 1990s through tightly controlled electronic platforms that inhibited more competitive trading — a new allegation that wasn’t in the original suit but mirrors similar complaints filed against banks in other markets, like stock loans.
The amended suit tightens its focus on a select number of banks, naming Goldman Sachs, Morgan Stanley, the Royal Bank of Scotland, BNP Paribas, and UBS, among others, as the firms behind the rigging, which they allege occurred from Jan. 1, 2007, to mid-2015.