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Expired European patentEurope

Lithographic mask for ions, electrons or X-rays, and process for its production

EP 0244496 B1 · Applicant: International Business Machines Corporation

EPO PDF

Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

Read the whole patent

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 May 6, 1986 and granted January 16, 1991. A European patent lasts at most 20 years from filing, so its term ended May 6, 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 November 6, 2011.
  • 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.
FiledMay 6, 1986
PublishedNovember 11, 1987
GrantedJanuary 16, 1991
Term endedMay 6, 2006
Application numberEP 86106188
Classification (CPC)G03F1/20 +2 more

Timeline

Timeline From EPO dates

1987198919911993199519971999200120032005Application filedMay 6, 1986PublishedNov 11, 1987Patent grantedJan 16, 1991Term endedMay 6, 2006

Sources & verification