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Expired European patentEurope

Test method for ferromagnetic powders

EP 0040323 B1 · Applicant: HOECHST AKTIENGESELLSCHAFT

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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 11, 1981 and granted September 12, 1984. A European patent lasts at most 20 years from filing, so its term ended April 11, 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 October 11, 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.
FiledApril 11, 1981
PublishedNovember 25, 1981
GrantedSeptember 12, 1984
Term endedApril 11, 2001
Application numberEP 81102800
Classification (CPC)B03B13/005 +2 more

Timeline

Timeline From EPO dates

1982198419861988199019921994199619982000Application filedApril 11, 1981PublishedNov 25, 1981Patent grantedSep 12, 1984Term endedApril 11, 2001

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