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Expired European patentEurope

Method for making optical fiber preforms

EP 0656325 B1 · Applicant: AT&T Corp.

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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 November 16, 1994 and granted September 22, 1999. A European patent lasts at most 20 years from filing, so its term ended November 16, 2014.
  • 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 May 16, 2020.
  • 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.
FiledNovember 16, 1994
PublishedJune 7, 1995
GrantedSeptember 22, 1999
Term endedNovember 16, 2014
Application numberEP 94308471
Classification (CPC)C03B23/207 +2 more

Timeline

Timeline From EPO dates

1995199719992001200320052007200920112013Application filedNov 16, 1994PublishedJune 7, 1995Patent grantedSep 22, 1999Term endedNov 16, 2014

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.