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Expired European patentEurope

Filter element comprising filter material either pleated in zig-zag fashion or in the shape of a star or a slab

EP 0447875 B1 · Applicant: KNECHT FILTERWERKE GMBH

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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 March 6, 1991 and granted September 14, 1994. A European patent lasts at most 20 years from filing, so its term ended March 6, 2011.
  • 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 September 6, 2016.
  • 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.
FiledMarch 6, 1991
PublishedSeptember 25, 1991
GrantedSeptember 14, 1994
Term endedMarch 6, 2011
Application numberEP 91103359
Classification (CPC)B01D29/111 +1 more

Timeline

Timeline From EPO dates

1992199419961998200020022004200620082010Application filedMarch 6, 1991PublishedSep 25, 1991Patent grantedSep 14, 1994Term endedMarch 6, 2011

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