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Expired European patentEurope

Improvements in the manufacture of group IIIB-VB compounds

EP 0052979 B1 · Applicant: BRITISH TELECOMMUNICATIONS public limited 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 November 10, 1981 and granted September 18, 1985. A European patent lasts at most 20 years from filing, so its term ended November 10, 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 May 10, 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.
FiledNovember 10, 1981
PublishedJune 2, 1982
GrantedSeptember 18, 1985
Term endedNovember 10, 2001
Application numberEP 81305334
Classification (CPC)C23C16/06 +2 more

Timeline

Timeline From EPO dates

1982198419861988199019921994199619982000Application filedNov 10, 1981PublishedJune 2, 1982Patent grantedSep 18, 1985Term endedNov 10, 2001

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