On behalf of the Project Company, the Preferred Bidder will be required to provide the Government Entity a Development Security equal to a certain percentage of the EPC Contract Price, as determined by the Authority. The Development Security must be an irrevocable and unconditional guarantee issued by a recognised bank or banks having a long-term unsecured credit rating that is "investment-grade", which can be defined as possessing a "BBB" or the equivalent from Standard & Poor's Rating Services or "Baa2" or the equivalent from Moody's Investor Services, Inc.