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EP 0033475 B1 · Applicant: Kümmerlin, Helga

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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.

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Why it's free to use

  • Filed January 21, 1981 and granted November 30, 1983. A European patent lasts at most 20 years from filing, so its term ended January 21, 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 July 21, 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.
FiledJanuary 21, 1981
PublishedAugust 12, 1981
GrantedNovember 30, 1983
Term endedJanuary 21, 2001
Application numberEP 81100404
Classification (CPC)E06C1/387 +2 more

Timeline

Timeline From EPO dates

1982198419861988199019921994199619982000Application filedJan 21, 1981PublishedAug 12, 1981Patent grantedNov 30, 1983Term endedJan 21, 2001

Sources & verification

Official EPO records

Full published documentClaims, description and drawings as a PDF.EPOEuropean Patent RegisterProcedure, status, file inspection and legal events.EPOLinked open EP data recordThe bibliographic record this page is built from.EPO

Cross-check elsewhere

Google PatentsFull text, worldwide family, citing patents and legal events.patents.google.comEspacenetNational family members and their legal status.European Patent Office

Everything on this page comes from the EPO record linked above. EPO data used under CC BY 4.0.