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Expired European patentEurope

Power amplifier

EP 0255652 B1 · Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

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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 21, 1987 and granted October 19, 1994. A European patent lasts at most 20 years from filing, so its term ended July 21, 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 January 21, 2013.
  • 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 21, 1987
PublishedFebruary 10, 1988
GrantedOctober 19, 1994
Term endedJuly 21, 2007
Application numberEP 87110559
Classification (CPC)H03F3/604 +1 more

Timeline

Timeline From EPO dates

1988199019921994199619982000200220042006Application filedJuly 21, 1987PublishedFeb 10, 1988Patent grantedOct 19, 1994Term endedJuly 21, 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.