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Expired European patentEurope

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EP 0269617 B1 · Applicant: AT&T Corp.

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Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

Read the whole patent

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 May 30, 1986 and granted January 24, 1990. A European patent lasts at most 20 years from filing, so its term ended May 30, 2006.
  • 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 November 30, 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.
FiledMay 30, 1986
PublishedJune 8, 1988
GrantedJanuary 24, 1990
Term endedMay 30, 2006
Application numberEP 86903940
Classification (CPC)H01F27/2866

Timeline

Timeline From EPO dates

1987198919911993199519971999200120032005Application filedMay 30, 1986PublishedJune 8, 1988Patent grantedJan 24, 1990Term endedMay 30, 2006

Sources & verification