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Expired European patentEurope

Retrievable inside blowout preventer valve apparatus

EP 0121566 B1 · Applicant: HYDRIL COMPANY

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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 October 12, 1983 and granted August 27, 1986. A European patent lasts at most 20 years from filing, so its term ended October 12, 2003.
  • 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 12, 2009.
  • 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 12, 1983
PublishedOctober 17, 1984
GrantedAugust 27, 1986
Term endedOctober 12, 2003
Application numberEP 83903662
Classification (CPC)E21B21/10 +2 more

Timeline

Timeline From EPO dates

1984198619881990199219941996199820002002Application filedOct 12, 1983PublishedOct 17, 1984Patent grantedAug 27, 1986Term endedOct 12, 2003

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