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EP 0249623 B1 · Applicant: Hughes Aircraft 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.

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Why it's free to use

  • Filed November 17, 1986 and granted December 27, 1991. A European patent lasts at most 20 years from filing, so its term ended November 17, 2006.
  • 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 17, 2012.
  • 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 17, 1986
PublishedDecember 23, 1987
GrantedDecember 27, 1991
Term endedNovember 17, 2006
Application numberEP 87900394
Classification (CPC)H03H19/00

Timeline

Timeline From EPO dates

1987198919911993199519971999200120032005Application filedNov 17, 1986PublishedDec 23, 1987Patent grantedDec 27, 1991Term endedNov 17, 2006

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.