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Expired European patentEurope

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EP 0107331 B1 · Applicant: Western Electric Company, Incorporated

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Overview

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

Read the whole patent

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 September 19, 1983 and granted July 6, 1988. A European patent lasts at most 20 years from filing, so its term ended September 19, 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 March 19, 2009.
  • 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.
FiledSeptember 19, 1983
PublishedMay 2, 1984
GrantedJuly 6, 1988
Term endedSeptember 19, 2003
Application numberEP 83305477
Classification (CPC)G03F1/62 +1 more

Timeline

Timeline From EPO dates

1984198619881990199219941996199820002002Application filedSep 19, 1983PublishedMay 2, 1984Patent grantedJuly 6, 1988Term endedSep 19, 2003

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