Expired European patentEurope
Pregrooved information medium with offset pits, method of making the pits, method for extracting a tracting error signal and reproducing apparatus for realizing this method
EP 0453343 B1 · Applicant: ART TECH GIGADISC ATG
Overview
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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 March 29, 1991 and granted July 16, 1997. A European patent lasts at most 20 years from filing, so its term ended March 29, 2011.
- 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 September 29, 2016.
- 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.
FiledMarch 29, 1991
PublishedOctober 23, 1991
GrantedJuly 16, 1997
Term endedMarch 29, 2011
Application numberEP 91400858
Classification (CPC)G11B7/26 +2 more
Timeline
Timeline From EPO dates
Sources & verification
Official EPO records
Everything on this page comes from the EPO record linked above. EPO data used under CC BY 4.0.