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Expired European patentEurope

Semiconductor memory device

EP 0090331 B1 · Applicant: KABUSHIKI KAISHA TOSHIBA

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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 March 22, 1983 and granted April 17, 1991. A European patent lasts at most 20 years from filing, so its term ended March 22, 2003.
  • 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 September 22, 2008.
  • 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.
FiledMarch 22, 1983
PublishedOctober 5, 1983
GrantedApril 17, 1991
Term endedMarch 22, 2003
Application numberEP 83102836
Classification (CPC)G11C29/848

Timeline

Timeline From EPO dates

1984198619881990199219941996199820002002Application filedMarch 22, 1983PublishedOct 5, 1983Patent grantedApril 17, 1991Term endedMarch 22, 2003

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