A method for maintaining a cache of dynamically generated objects. The method includes storing in the cache dynamically generated objects previously served from an originating server to a client. A communication between the client and server is intercepted by the cache. The cache parses the communication to identify an object determinant and to determine whether the object determinant indicates whether a change has occurred or will occur in an object at the originating server. The cache marks the object stored in the cache as invalid if the object determinant so indicates. If the object has been marked as invalid, the cache retrieves the object from the originating server.