A system and method for filtering of web-based content in a proxy cache server environment provides a local network having a client, a directory server and a proxy cache server that caches predetermined Internet-derived web content within the network. When content is requested, it is vended to the client only if it meets predefined user policies for acceptability. These policies are implemented based upon one or more ratings lists provided by content rating vendors. The lists are downloaded to the network in whole or part, and cached for use in determining acceptability of content by a filter application. Ratings can be particularly based upon predetermined content categories. Caching occurs in a host or object cache for rapid access. Only if current ratings are not found in the host or object caches are ratings caches or vendors accessed for ratings. Ratings on requested content are then placed in the host or object cache for subsequent use. Object parsing or other techniques can be used to screen returned content that is unrated or otherwise allowed to pass to ensure that it is appropriate.