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Expired European patentEurope

Selective dealumination of zeolites

EP 0171981 B1 · Applicant: The British Petroleum Company p.l.c.

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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 August 1, 1985 and granted March 23, 1988. A European patent lasts at most 20 years from filing, so its term ended August 1, 2005.
  • 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 February 1, 2011.
  • 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.
FiledAugust 1, 1985
PublishedFebruary 19, 1986
GrantedMarch 23, 1988
Term endedAugust 1, 2005
Application numberEP 85305493
Classification (CPC)C07C2/00

Timeline

Timeline From EPO dates

1986198819901992199419961998200020022004Application filedAug 1, 1985PublishedFeb 19, 1986Patent grantedMarch 23, 1988Term endedAug 1, 2005

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