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Expired European patentEurope

Method for improved focusing control in an optical memory system

EP 0077641 B1 · Applicant: BURROUGHS CORPORATION (a Delaware 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.

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Why it's free to use

  • Filed October 14, 1982 and granted December 30, 1986. A European patent lasts at most 20 years from filing, so its term ended October 14, 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 April 14, 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.
FiledOctober 14, 1982
PublishedApril 27, 1983
GrantedDecember 30, 1986
Term endedOctober 14, 2002
Application numberEP 82305460
Classification (CPC)G11B7/09 +2 more

Timeline

Timeline From EPO dates

1983198519871989199119931995199719992001Application filedOct 14, 1982PublishedApril 27, 1983Patent grantedDec 30, 1986Term endedOct 14, 2002

Sources & verification

Official EPO records

Full published documentClaims, description and drawings as a PDF.EPOEuropean Patent RegisterProcedure, status, file inspection and legal events.EPOLinked open EP data recordThe bibliographic record this page is built from.EPO

Cross-check elsewhere

Google PatentsFull text, worldwide family, citing patents and legal events.patents.google.comEspacenetNational family members and their legal status.European Patent Office

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