Pursuant to the Trade Sanctions Reform and Export Enhancement Act of 2000, you must sign the contract within 12 months of receiving authorization from the Bureau of Industry and Security (BIS) to export agricultural commodities to Cuba.  You have an additional 12 months from the signing of the contract to export the agricultural commodities to Cuba.  Alternatively, you may sign the contract before receiving export authorization from BIS, but you are still required to obtain BIS authorization prior to exporting the agricultural commodities and must export them within 12 months of the signing of the contract.  However, you are not required to sign a contract for exports to Cuba of agricultural commodities that are donated or commercial samples, but you must still obtain BIS authorization to export them and must do so within 12 months of receiving BIS authorization.