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EP 0052236 B1 · Applicant: SIEMENS AKTIENGESELLSCHAFT

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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 15, 1981 and granted May 2, 1985. A European patent lasts at most 20 years from filing, so its term ended October 15, 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 April 15, 2007.
  • 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 15, 1981
PublishedMay 26, 1982
GrantedMay 2, 1985
Term endedOctober 15, 2001
Application numberEP 81108368
Classification (CPC)G10H1/26 +1 more

Timeline

Timeline From EPO dates

1982198419861988199019921994199619982000Application filedOct 15, 1981PublishedMay 26, 1982Patent grantedMay 2, 1985Term endedOct 15, 2001

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