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Expired European patentEurope

Improved coal liquefaction process

EP 0073866 B1 · Applicant: Ruhrkohle Aktiengesellschaft

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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 December 21, 1981 and granted June 1, 1988. A European patent lasts at most 20 years from filing, so its term ended December 21, 2001.
  • 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 June 21, 2007.
  • 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.
FiledDecember 21, 1981
PublishedMarch 16, 1983
GrantedJune 1, 1988
Term endedDecember 21, 2001
Application numberEP 81305988
Classification (CPC)C10G1/065 +1 more

Timeline

Timeline From EPO dates

1982198419861988199019921994199619982000Application filedDec 21, 1981PublishedMarch 16, 1983Patent grantedJune 1, 1988Term endedDec 21, 2001

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