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USPTO - forward vs backward citation data

  • 07 May 2021 3:24 PM
    Reply # 10452697 on 10406226

    I have noticed the same thing. You can do a ref/xxx on patft's advanced search page to see what patents cite patent xxx. The patentsview api can also be used. It can return the list of cited_patent_numbers and list of citedby_patent_numbers. Their database is reloaded quarterly, so the citedby_patent_number list isn't always as complete as a ref/xxx search would be. The patentsview data is also available as a bulk download (uspatentcitation on


  • 29 Apr 2021 6:38 PM
    Message # 10406226

    To all - I have from time to time noticed the USPTO may list Patent A (being a US patent) as a backward citation to Patent B (also a US patent), but not Patent B as a forward citation to Patent A.  This is based on data published at the USPTO Patent Full-Text and Image Database, for Patent A and Patent B. 

    Has anyone else noticed this, and if so, does anyone have any comments on this? 

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