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Expired European patentEurope

Process for the preparation of the magnesium salt of 2-nitronaphthalene-4,8-disulphonic acid

EP 0014366 B1 · Applicant: BAYER AG

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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 January 21, 1980 and granted September 16, 1981. A European patent lasts at most 20 years from filing, so its term ended January 21, 2000.
  • 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 July 21, 2005.
  • 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.
FiledJanuary 21, 1980
PublishedAugust 20, 1980
GrantedSeptember 16, 1981
Term endedJanuary 21, 2000
Application numberEP 80100275
Classification (CPC)C07C309/00

Timeline

Timeline From EPO dates

1981198319851987198919911993199519971999Application filedJan 21, 1980PublishedAug 20, 1980Patent grantedSep 16, 1981Term endedJan 21, 2000

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.