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Expired European patentEurope

Liquid crystal display device and phase difference plates

EP 0478779 B1 · Applicant: Citizen Watch Co. Ltd.

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Overview

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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 June 20, 1990 and granted November 2, 1994. A European patent lasts at most 20 years from filing, so its term ended June 20, 2010.
  • 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 December 20, 2015.
  • 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.
FiledJune 20, 1990
PublishedApril 8, 1992
GrantedNovember 2, 1994
Term endedJune 20, 2010
Application numberEP 90909399
Classification (CPC)G02F1/13363

Timeline

Timeline From EPO dates

1991199319951997199920012003200520072009Application filedJune 20, 1990PublishedApril 8, 1992Patent grantedNov 2, 1994Term endedJune 20, 2010

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