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Expired European patentEurope

Polyquinoxaline compositions and their method of preparation

EP 0444807 B1 · Applicant: EXXON RESEARCH AND ENGINEERING COMPANY

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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 February 18, 1991 and granted August 24, 1994. A European patent lasts at most 20 years from filing, so its term ended February 18, 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 August 18, 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.
FiledFebruary 18, 1991
PublishedSeptember 4, 1991
GrantedAugust 24, 1994
Term endedFebruary 18, 2011
Application numberEP 91301280
Classification (CPC)C08G73/0694

Timeline

Timeline From EPO dates

1992199419961998200020022004200620082010Application filedFeb 18, 1991PublishedSep 4, 1991Patent grantedAug 24, 1994Term endedFeb 18, 2011

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

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