07120250 is referenced by 125 patents and cites 279 patents.

A method and apparatus for enabling use of multiple digital rights management scenarios (DRM). Unencrypted data representing digital content is examined to identify at least segments of content for encryption. The identified segments of content are duplicated and then encrypted using a first encryption method associated with a first DRM to produce first encrypted segments. Duplicates are encrypted using a second encryption method associated with a second DRM to produce second encrypted segments. A set of pointers are generated that point to the first and second encrypted segments content. A file is then created containing first and second encrypted segments of content, pointers and unencrypted content along with DRM rights data to produce a selectively encrypted multiple DRM enabled file.

Title
Content distribution for multiple digital rights management
Application Number
10/318782
Publication Number
7120250 (B2)
Application Date
December 13, 2002
Publication Date
October 10, 2006
Inventor
Brant L Candelore
Escondido
CA, US
Agent
Jerry A Miller
Miller Patent Services
Assignee
Sony Electronics
NJ, US
Sony Corporation
JP
IPC
H04N 7/167
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