As used for gas, the agent responsible for ascertaining the apportionment of natural gas between a gas buyer and other buyers of natural gas at a system entry point (such as a gas reception terminal at the beach). The CVA is responsible for providing delivery information to the National Gas Transmission (NGT) pursuant to the provisions of the Claims Validation Agency Agreement in force for the system entry point. The role was created in 1996 under the original Network Code (now the Uniform Network Code) and was carried out by PricewaterhouseCoopers until 2004. For more information, see Gas Management Services Limited: CVA.