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Expired European patentEurope

Device for transmitting radio communication signals in a secondary radar system

EP 0021862 B1 · Applicant: THOMSON-CSF

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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.

Why it's free to use

  • Filed April 21, 1980 and granted November 30, 1983. A European patent lasts at most 20 years from filing, so its term ended April 21, 2000.
  • 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 21, 2005.
  • 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 21, 1980
PublishedJanuary 7, 1981
GrantedNovember 30, 1983
Term endedApril 21, 2000
Application numberEP 80400538
Classification (CPC)H01Q21/28 +1 more

Timeline

Timeline From EPO dates

1981198319851987198919911993199519971999Application filedApril 21, 1980PublishedJan 7, 1981Patent grantedNov 30, 1983Term endedApril 21, 2000

Sources & verification