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Expired European patentEurope

Process for the preparation of guanine and its alcalnic metal salts

EP 0541003 B1 · Applicant: BOEHRINGER INGELHEIM KG

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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 October 29, 1992 and granted January 20, 1999. A European patent lasts at most 20 years from filing, so its term ended October 29, 2012.
  • 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 April 29, 2018.
  • 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.
FiledOctober 29, 1992
PublishedMay 12, 1993
GrantedJanuary 20, 1999
Term endedOctober 29, 2012
Application numberEP 92118483
Classification (CPC)C07D473/18

Timeline

Timeline From EPO dates

1993199519971999200120032005200720092011Application filedOct 29, 1992PublishedMay 12, 1993Patent grantedJan 20, 1999Term endedOct 29, 2012

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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