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Expired European patentEurope

Implementing a shared higher level of privilege on personal computers for copy protection of software

EP 0174472 B1 · Applicant: International Business Machines Corporation

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Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

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Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed July 23, 1985 and granted November 18, 1993. A European patent lasts at most 20 years from filing, so its term ended July 23, 2005.
  • A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by January 23, 2011.
  • We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.
FiledJuly 23, 1985
PublishedMarch 19, 1986
GrantedNovember 18, 1993
Term endedJuly 23, 2005
Application numberEP 85109182
Classification (CPC)G06F21/123

Timeline

Timeline From EPO dates

1986198819901992199419961998200020022004Application filedJuly 23, 1985PublishedMarch 19, 1986Patent grantedNov 18, 1993Term endedJuly 23, 2005

Sources & verification