Patent ID: 7222232

Claim:
A computer-readable medium storing computer-executable instructions for performing steps comprising: controlling use of watermarked software objects, wherein a predefined watermark key is stored which defines a specific one of a plurality of identical watermarks embedded in a watermarked software object with different watermark keys to be used in subsequently controlling use of each of the watermarked software objects and wherein the predefined watermark key expires after a predefined period of time elapses since the predefined watermark key was initially stored; establishing a network connection to a server; issuing a request to the server for a new watermark key; utilizing either the predefined watermark key or the new watermark key, as received from the server, for the predefined watermark key for subsequent use in controlling access to the watermarked software objects until such time as the predefined key has expired after which the new watermark key is used instead; selecting, if the predefined watermark key has not been revoked for a client computer, another one of predefined plurality of predetermined watermark keys for use in controlling access to the software watermarks objects as the new watermark key; sending the new watermark key to the client computer; and if the predefined watermark key has been revoked, does not supply the new watermark key to the client computer.