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EP 0336938 B1 · Applicant: BRITISH TELECOMMUNICATIONS public limited company

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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 August 26, 1988 and granted December 2, 1992. A European patent lasts at most 20 years from filing, so its term ended August 26, 2008.
  • 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 February 26, 2014.
  • 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.
FiledAugust 26, 1988
PublishedOctober 18, 1989
GrantedDecember 2, 1992
Term endedAugust 26, 2008
Application numberEP 88907754
Classification (CPC)G02B6/4439 +2 more

Timeline

Timeline From EPO dates

1989199119931995199719992001200320052007Application filedAug 26, 1988PublishedOct 18, 1989Patent grantedDec 2, 1992Term endedAug 26, 2008

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.