06714921 is referenced by 102 patents and cites 32 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
9/778006
Publication Number
6714921 (B2)
Application Date
February 7, 2001
Publication Date
March 30, 2004
Inventor
Peter L T Pirolli
El Cerrito
CA, US
Mark J Stefik
Woodside
CA, US
Agent
Nixon Peabody
US
Agent
Marc S Kaufman Esq
US
Assignee
ContentGuard
MD, US
IPC
G06F 17/60
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