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Expired European patentEurope

Pretreatment of overwritable opto-magnetic recording medium and pretreated overwritable opto-magnetic recording medium

EP 0451297 B1 · Applicant: NIKON CORPORATION

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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 October 31, 1990 and granted December 13, 1995. A European patent lasts at most 20 years from filing, so its term ended October 31, 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 May 1, 2016.
  • 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.
FiledOctober 31, 1990
PublishedOctober 16, 1991
GrantedDecember 13, 1995
Term endedOctober 31, 2010
Application numberEP 90916077
Classification (CPC)G11B19/12 +2 more

Timeline

Timeline From EPO dates

1991199319951997199920012003200520072009Application filedOct 31, 1990PublishedOct 16, 1991Patent grantedDec 13, 1995Term endedOct 31, 2010

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