05222134 is referenced by 550 patents and cites 13 patents.

A process and system for activating various programs are provided in a personal computer. The computer is initially provided with a registration shell. A data link is established between the personal computer and a registration computer. By providing the registration computer with various information, a potential licensee can register to utilize the program. Once the registration process is complete, a tamperproof overlay program is constructed at the registration computer and transferred to the personal computer. The tamperproof overlay includes critical portions of the main program, without which the main program would not operate and also contains licensee identification and license control data.

Title
Secure system for activating personal computer software at remote locations
Application Number
610037
Publication Number
5222134
Application Date
April 9, 1991
Publication Date
June 22, 1993
Inventor
Horace G Riddell
Chantilly
VA, US
David P Waite
Fairfax
VA, US
Agent
Hoffman Wasson & Gitler
Assignee
Tau Systems Corporation
VA, US
IPC
H04L 9/32
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