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Expired European patentEurope

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EP 0073136 B1 · Applicant: KONICA CORPORATION

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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 August 18, 1982 and granted November 12, 1986. A European patent lasts at most 20 years from filing, so its term ended August 18, 2002.
  • 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 February 18, 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.
FiledAugust 18, 1982
PublishedMarch 2, 1983
GrantedNovember 12, 1986
Term endedAugust 18, 2002
Application numberEP 82304358
Classification (CPC)G03F1/54

Timeline

Timeline From EPO dates

1983198519871989199119931995199719992001Application filedAug 18, 1982PublishedMarch 2, 1983Patent grantedNov 12, 1986Term endedAug 18, 2002

Sources & verification