A method, system, and software for state signing of Internet resources is presented in which web pages and other Internet resources are signed after the insertion of metadata indicating intended and authorized uses. In one embodiment, the signing is accomplished through use of a cryptographic signature added to any data item passed to a client that is likely to be passed back to the server later, such as a cookie, URL, or data integrity item. Enabling and disabling of state signing for various data items can be controlled through policies tied to URL prefixes.