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Expired European patentEurope

Improvements in or relating to cutting elements for rotary drill bits

EP 0384623 B1 · Applicant: CAMCO DRILLING GROUP LIMITED

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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 February 12, 1990 and granted March 2, 1994. A European patent lasts at most 20 years from filing, so its term ended February 12, 2010.
  • 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 August 12, 2015.
  • 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.
FiledFebruary 12, 1990
PublishedAugust 29, 1990
GrantedMarch 2, 1994
Term endedFebruary 12, 2010
Application numberEP 90301437
Classification (CPC)C04B37/001 +2 more

Timeline

Timeline From EPO dates

1991199319951997199920012003200520072009Application filedFeb 12, 1990PublishedAug 29, 1990Patent grantedMarch 2, 1994Term endedFeb 12, 2010

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