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Expired European patentEurope

Method of preparing a gas containing a high portion of methane

EP 0028835 B1 · Applicant: VEG-GASINSTITUUT N.V.

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Overview

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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 November 10, 1980 and granted May 18, 1983. A European patent lasts at most 20 years from filing, so its term ended November 10, 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 May 10, 2006.
  • 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.
FiledNovember 10, 1980
PublishedMay 20, 1981
GrantedMay 18, 1983
Term endedNovember 10, 2000
Application numberEP 80106929
Classification (CPC)C07C4/00 +2 more

Timeline

Timeline From EPO dates

1981198319851987198919911993199519971999Application filedNov 10, 1980PublishedMay 20, 1981Patent grantedMay 18, 1983Term endedNov 10, 2000

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