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Expired European patentEurope

Photochromic compounds

EP 0232295 B1 · Applicant: Optische Werke G. Rodenstock

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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.

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Why it's free to use

  • Filed July 21, 1986 and granted June 16, 1993. A European patent lasts at most 20 years from filing, so its term ended July 21, 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 January 21, 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.
FiledJuly 21, 1986
PublishedAugust 19, 1987
GrantedJune 16, 1993
Term endedJuly 21, 2006
Application numberEP 86904109
Classification (CPC)C07D498/22 +2 more

Timeline

Timeline From EPO dates

1987198919911993199519971999200120032005Application filedJuly 21, 1986PublishedAug 19, 1987Patent grantedJune 16, 1993Term endedJuly 21, 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.