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Expired Australian patentAustralia

Optical attenuator

AU 1981069367 · Applicant: Ferranti Limited

AusPat record

Overview

Drawings and full text

Its specification, documents and status are on IP Australia's AusPat.

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Listed from its IP Australia record in Patent Yard's archive of Australian patents past their term. Its claims, description and drawings are in the AusPat record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed April 10, 1981 and granted February 23, 1984. An Australian standard patent lasts 20 years from its date of patent, which is at most a year after this filing, so its term ended by April 10, 2002.
  • A pharmaceutical extension adds at most five years, so even that would have ended by April 10, 2007.
  • We check Australian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledApril 10, 1981
GrantedFebruary 23, 1984
Term ended byApril 10, 2002
Application numberAU 1981069367
Classification (IPC)G02B5/04 +2 more

Timeline

Timeline From IP Australia dates

1982198519881991199419972000Application filedApril 10, 1981Patent grantedFeb 23, 1984Term ended byApril 10, 2002

Sources & verification

Everything on this page comes from the IP Australia record linked above. Data from IP Australia's IPGOD, licensed under CC BY 2.5 AU.