Patent Yard Sign in
Expired European patentEurope

Echo cancelling device with phase-roll correction

EP 0287743 B1 · Applicant: International Business Machines Corporation

EPO PDF

Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

Read the whole patent

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.

Google PatentsEPO PDF

Why it's free to use

  • Filed April 22, 1987 and granted March 3, 1993. A European patent lasts at most 20 years from filing, so its term ended April 22, 2007.
  • 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 October 22, 2012.
  • 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.
FiledApril 22, 1987
PublishedOctober 26, 1988
GrantedMarch 3, 1993
Term endedApril 22, 2007
Application numberEP 87430015
Classification (CPC)H04B3/232

Timeline

Timeline From EPO dates

1988199019921994199619982000200220042006Application filedApril 22, 1987PublishedOct 26, 1988Patent grantedMarch 3, 1993Term endedApril 22, 2007

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.