Sen. Elizabeth Warren, D-Mass., and U.S. Rep. Alexandria Ocasio-Cortez, D-N.Y., sent letters to the 14 biggest depositors of Silicon Valley Bank Sunday, including BlockFi and Robox, asking them about their “cozy” relationship with the bank, Bloomberg reports.

The Democrats have questions about the bankrupt bank’s relationship with the venture capitalist, private equity and technology customers, the amount of money they deposited with SVB and whether they had received any special benefits. Warren and AOC want to know if members of the companies’ boards, executives or investors were given such benefits as flexible lines of credit.

“Silicon Valley Bank’s unusually cozy relationship with its clients increased the threat of contagion when the bank went under,” Warren told Bloomberg. “The American people deserve to know how these mutual backscratching arrangements developed, who benefitted from them, and what role they played in Silicon Valley Bank’s failure.”

The 14 firms that received letters are: BILL, BlockFi, Circle, Eiger, Ginkgo Bioworks Inc., iRhythm Technologies Inc., LendingClub Corp., Oncorus Inc., Payoneer Global Inc., Protagonist Therapeutics Inc., Roblox Corp., Rocket Lab USA Inc., Roku Inc. and Sangamo Therapeutics Inc.

A Roblox spokesperson said the company will be replying to the two lawmakers “in a timely manner.” The other 13 companies didn’t immediately respond to Bloomberg requests for comment.

The U.S. government backstopped SVB immediately after it collapsed on March 10, 2023. First Citizens BankShares agreed to buy $72 billion of SVB’s assets later in the month. Roughly $90 million in securities and assets remain with the Federal Deposit Insurance Corp.