Patent Yard Sign in
Expired European patentEurope

Modulator circuit

EP 0451372 B1 · Applicant: BELL TELEPHONE MANUFACTURING COMPANY Naamloze Vennootschap

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 13, 1990 and granted August 17, 1994. A European patent lasts at most 20 years from filing, so its term ended April 13, 2010.
  • 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 13, 2015.
  • 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 13, 1990
PublishedOctober 16, 1991
GrantedAugust 17, 1994
Term endedApril 13, 2010
Application numberEP 90200923
Classification (CPC)H03C1/545

Timeline

Timeline From EPO dates

1991199319951997199920012003200520072009Application filedApril 13, 1990PublishedOct 16, 1991Patent grantedAug 17, 1994Term endedApril 13, 2010

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.