Definitions of past consideration
(COMMON LAW SYSTEMS) consideration is anything given or promised by one party in exchange for the promise or action of another; it is an essential element of a binding contract in common law systems, and must not me from the past. For example, if A promises to pay B for something that B has already performed (before the promise was made), the performance of B's act is past consideration and is not good consideration.
The courts will typically not permit past consideration for a current transaction and will void an agreement if it was based on past consideration.