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Expired European patentEurope

Method and apparatus for recording and reproducing a digital signal with a stationary head

EP 0169540 B1 · Applicant: HITACHI, LTD.

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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 July 23, 1985 and granted January 3, 1990. A European patent lasts at most 20 years from filing, so its term ended July 23, 2005.
  • 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 January 23, 2011.
  • 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.
FiledJuly 23, 1985
PublishedJanuary 29, 1986
GrantedJanuary 3, 1990
Term endedJuly 23, 2005
Application numberEP 85109200
Classification (CPC)G11B20/1809

Timeline

Timeline From EPO dates

1986198819901992199419961998200020022004Application filedJuly 23, 1985PublishedJan 29, 1986Patent grantedJan 3, 1990Term endedJuly 23, 2005

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