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Expired European patentEurope

Electronic line equipment with two-wire-four-wire conversion circuit for telephone exchange

EP 0001522 B1 · Applicant: JEUMONT-SCHNEIDER Société anonyme dite:

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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 September 19, 1978 and granted April 7, 1982. A European patent lasts at most 20 years from filing, so its term ended September 19, 1998.
  • 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 March 19, 2004.
  • 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.
FiledSeptember 19, 1978
PublishedApril 18, 1979
GrantedApril 7, 1982
Term endedSeptember 19, 1998
Application numberEP 78400104
Classification (CPC)H04M19/005 +1 more

Timeline

Timeline From EPO dates

1979198119831985198719891991199319951997Application filedSep 19, 1978PublishedApril 18, 1979Patent grantedApril 7, 1982Term endedSep 19, 1998

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.