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Expired European patentEurope

Process for preparing acetic anhydride and eventually acetic acid

EP 0079461 B1 · Applicant: HOECHST 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 October 8, 1982 and granted December 5, 1984. A European patent lasts at most 20 years from filing, so its term ended October 8, 2002.
  • 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 April 8, 2008.
  • 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.
FiledOctober 8, 1982
PublishedMay 25, 1983
GrantedDecember 5, 1984
Term endedOctober 8, 2002
Application numberEP 82109323
Classification (CPC)C07C51/12 +1 more

Timeline

Timeline From EPO dates

1983198519871989199119931995199719992001Application filedOct 8, 1982PublishedMay 25, 1983Patent grantedDec 5, 1984Term endedOct 8, 2002

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