Proof of reserves is an audit method adopted by cryptocurrency exchanges in the aftermath of FTX’s collapse to prove that the custodian, in this case, OKX, isn’t lending out customer funds, as FTX did, and has the assets it claims to hold on behalf of its users. They have, nevertheless, been criticized for not providing information about liabilities and internal quality controls, a focal point in the crypto community. For instance, Binance’s recent proof of reserves report from French audit firm Mazars was criticized for lack of details about the way exchange liquidates assets to cover margin loans.