06236971 is referenced by 465 patents and cites 6 patents.

A system for controlling the distribution and use of digital works using digital tickets. In the present invention, a “digital ticket” is used to entitle the ticket holder to exercise some usage right with respect to a digital work. Usage rights are used to define how a digital work may be used or distributed. Each usage right may specify a digital ticket which must be present before the right may be exercised. Digital works are stored in repositories which enforce a digital works usage rights. Each repository has a “generic ticket agent” which punches tickets. In some instances only the generic ticket agent is necessary. In other instances, punching by a “special ticket agent” residing on another repository may be needed.

Title
System for controlling the distribution and use of digital works using digital tickets
Application Number
8/967084
Publication Number
6236971 (B1)
Application Date
November 10, 1997
Publication Date
May 22, 2001
Inventor
Peter L T Pirolli
El Cerrito
CA, US
Mark J Stefik
Woodside
CA, US
Agent
Nixon Peabody
US
Agent
Marc S Kaufman
US
Assignee
Xerox Corporation
CT, US
Contentguard Holdings
DE, US
IPC
G06F 17/60
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