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EP 0823809 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

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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 July 15, 1997 and granted April 2, 2003. A European patent lasts at most 20 years from filing, so its term ended July 15, 2017.
  • 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 January 15, 2023.
  • 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.
FiledJuly 15, 1997
PublishedFebruary 11, 1998
GrantedApril 2, 2003
Term endedJuly 15, 2017
Application numberEP 97112082
Classification (CPC)H04M3/4931

Timeline

Timeline From EPO dates

1998200020022004200620082010201220142016Application filedJuly 15, 1997PublishedFeb 11, 1998Patent grantedApril 2, 2003Term endedJuly 15, 2017

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.