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Expired European patentEurope

Digital data apparatus

EP 0021283 B1 · Applicant: International Business Machines Corporation

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Overview

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.

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Why it's free to use

  • Filed June 13, 1980 and granted January 29, 1986. A European patent lasts at most 20 years from filing, so its term ended June 13, 2000.
  • 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 December 13, 2005.
  • 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.
FiledJune 13, 1980
PublishedJanuary 7, 1981
GrantedJanuary 29, 1986
Term endedJune 13, 2000
Application numberEP 80103312
Classification (CPC)H04L1/004 +2 more

Timeline

Timeline From EPO dates

1981198319851987198919911993199519971999Application filedJune 13, 1980PublishedJan 7, 1981Patent grantedJan 29, 1986Term endedJune 13, 2000

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

Everything on this page comes from the EPO record linked above. EPO data used under CC BY 4.0.