What Is a Credit Support Annex (CSA)?
A CSA is a legally binding document that forms part of the ISDA Master Agreement. It governs the terms of collateral exchange between two parties in an OTC derivatives transaction.
It specifies the types of collateral accepted, the valuation methodology, the thresholds for posting collateral, and the timing of margin calls. The CSA is the risk management heart of an uncleared OTC trade.