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Expired European patentEurope

Photochromic naphthopyran compounds

EP 0755527 B1 · Applicant: PPG Industries Ohio, Inc.

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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 April 7, 1995 and granted March 15, 2000. A European patent lasts at most 20 years from filing, so its term ended April 7, 2015.
  • 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 October 7, 2020.
  • 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.
FiledApril 7, 1995
PublishedJanuary 29, 1997
GrantedMarch 15, 2000
Term endedApril 7, 2015
Application numberEP 95916270
Classification (CPC)C07D493/04 +2 more

Timeline

Timeline From EPO dates

1996199820002002200420062008201020122014Application filedApril 7, 1995PublishedJan 29, 1997Patent grantedMarch 15, 2000Term endedApril 7, 2015

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.