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Expired European patentEurope

Equipment for telephone interexchange signalling on PCM carrier realized by centralized-logic line-exchange interface units

EP 0002467 B1 · Applicant: CSELT Centro Studi e Laboratori Telecomunicazioni S.p.A.

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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.

Why it's free to use

  • Filed December 1, 1978 and granted March 31, 1982. A European patent lasts at most 20 years from filing, so its term ended December 1, 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 June 1, 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.
FiledDecember 1, 1978
PublishedJune 27, 1979
GrantedMarch 31, 1982
Term endedDecember 1, 1998
Application numberEP 78101498
Classification (CPC)H04Q11/04 +1 more

Timeline

Timeline From EPO dates

1979198119831985198719891991199319951997Application filedDec 1, 1978PublishedJune 27, 1979Patent grantedMarch 31, 1982Term endedDec 1, 1998

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