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Expired European patentEurope

Method for making a tunnel by using a driving shield

EP 0303775 B1 · Applicant: HOCHTIEF AKTIENGESELLSCHAFT VORM. GEBR. HELFMANN

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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 May 19, 1988 and granted March 4, 1992. A European patent lasts at most 20 years from filing, so its term ended May 19, 2008.
  • 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 November 19, 2013.
  • 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.
FiledMay 19, 1988
PublishedFebruary 22, 1989
GrantedMarch 4, 1992
Term endedMay 19, 2008
Application numberEP 88108029
Classification (CPC)E21D9/0635

Timeline

Timeline From EPO dates

1989199119931995199719992001200320052007Application filedMay 19, 1988PublishedFeb 22, 1989Patent grantedMarch 4, 1992Term endedMay 19, 2008

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