Patent · US Expired

Illegal copy prevention apparatus

US5295187A · kind A · utility

15Cited by
5References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 5, 1991
Grant dateMar 15, 1994
Priority date
Expiry dateDec 5, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F21/121
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An illegal copy prevention apparatus including a plurality of illegal copy discriminators (e.g. instructions to set flags), an event generator (e.g. detections of "0" sec in real time) corresponding to the illegal copy discriminators, and an abnormal operation generator for generating an abnormal operation when any one of the illegal discriminator and the corresponding event generator generates an event. Since the probability at which all the abnormal operations are generated by all the abnormal operation generators is low, it is extremely difficult for a violator to notice the presence of all the copy protections and further remove all the copy protections completely, thus realizing an effective illegal copy prevention apparatus for computer software and circuit configuration of IC devices.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.