17 CFR 22.7: Permitted depositories: Treatment of Cleared Swaps Customer Collateral.

A Permitted Depository shall treat all funds in a Cleared Swaps Customer Account as Cleared Swaps Customer Collateral. A Permitted Depository shall not hold, dispose of, or use any such Cleared Swaps Customer Collateral as belonging to any person other than:

(a) The Cleared Swaps Customers of the futures commission merchant maintaining such Cleared Swaps Customer Account or;

(b) The Cleared Swaps Customers of the futures commission merchants for which the derivatives clearing organization maintains such Cleared Swaps Customer Account.