05199066 is referenced by 193 patents and cites 16 patents.

A method and system for protecting a software program recorded within a storage medium for use with or transmission to computer or processor based hardware comprises inputting a hardware code uniquely associated with the particular hardware and inputting a first software code uniquely associated with the particular embodiment of the software. A first predetermined operation is performed upon the hardware code and the first software code to produce an intermediate code. A unique activation code obtained from the software supplier is inputted and a second predetermined operation is performed upon the intermediate code and the activation code to produce a second intermediate code. The second intermediate code is compared to a second software code uniquely associated with the particular embodiment of the software and stored in a hidden location within the software. The use of the software is enabled only if the second intermediate code and the second software code are identical.

Title
Method and apparatus for protecting software
Application Number
7/339760
Publication Number
5199066
Application Date
April 18, 1989
Publication Date
March 30, 1993
Inventor
Andrew J Logan
Gladwyne
PA, US
Agent
Woodcock Washburn Kurtz Mackiewicz & Norris
Assignee
Special Effects Software
PA, US
IPC
H04L 9/32
H04L 9/00
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