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Expired European patentEurope

Photomask and method of testing it

EP 0066466 B1 · Applicant: FUJITSU LIMITED

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 28, 1982 and granted April 16, 1986. A European patent lasts at most 20 years from filing, so its term ended May 28, 2002.
  • 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 28, 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.
FiledMay 28, 1982
PublishedDecember 8, 1982
GrantedApril 16, 1986
Term endedMay 28, 2002
Application numberEP 82302777
Classification (CPC)G03F1/44 +2 more

Timeline

Timeline From EPO dates

1983198519871989199119931995199719992001Application filedMay 28, 1982PublishedDec 8, 1982Patent grantedApril 16, 1986Term endedMay 28, 2002

Sources & verification