Senator Elizabeth Warren and Representative Alexandria Ocasio-Cortez sent letters to 14 of Silicon Valley Bank's largest depositors, including Circle Internet Financial, BILL Holdings, BlockFi, and Eiger BioPharmaceuticals, asking about their connections with the failed bank.

Warren and Ocasio-Cortez are concerned about reports that SVB had a cozy relationship with some of its largest venture capitalists and provided them with special perks, while the VC firms in return gave the bank access to huge unsecured sources of short-term funding. The lawmakers want to know whether board members, executives, or investors had received special benefits from SVB.

The 14 firms have until April 24 to respond. SVB's collapse triggered a backstop by the federal government, and First Citizens BancShares agreed to buy $72 billion worth of SVB's assets in March.