Patents get withdrawn from time to time. Some are never issued but some are withdrawn after being issued. In the latter case, data for the withdrawn patent can be found in the wild. The patent office maintains a list of withdrawn patents at http://www.uspto.gov/patents-application-process/patent-search/withdrawn-patent-number Separately, the patentsview api team processes the bulk grant patent xml files and makes their files available for download. If one compares the patentsview patent.tsv file to the patent office’s withdrawn patent list, one finds (or found at the time this was written) 7,930 patents in both files. The patent office removes withdrawn patents from its web site, they are not returned by searches but this is not the case with the patentsview api. It will return withdrawn patents, which is pretty bizarre. I don’t know of another patent platform that does that. I raised a git issue to point this out to the otherwise fine patentsview folks but nothing has changed. (Two take-aways here, one that there is data for withdrawn patents in the grant xml files and the other is that patentsview loads them into their database.)
Another source of data for withdrawn patents is the USPat dvds once produced by the patent office. The data is available for download as thousands of zip files containing tiff images of patents, both withdrawn ones and ones that were not withdrawn. In the zip files I have analyzed, I have found 5,191 withdrawn patents among the millions of patents that have not been withdrawn.
The last source that I know of for data on withdrawn patents is the Official Gazettes (OGs) produced by the patent office each week. Some patents appear in the OGS that are subsequently withdrawn. An example would be PP31,892 which would have been issued on June 23, 2020. That patent wasn’t in the grant xml for the patents granted on June 23, 2020 but it did appear the OG for that date. It is also listed on the patent office’s withdrawn patent page. Interestingly, PP31,893 was also withdrawn but it is not present in xml file for June 23, 2020 and the OG says “Patent Not Issued For This Number”. Above is an image that shows the OG entries for these two withdrawn patents.
A possible source, that I haven’t fully investigated, is Hathi Trust. They have scanned many of the OGs that were physically published. The last printed OG was September 24, 2002, more recent ones are only published electronically.
So if you are interested in withdrawn patents, they are out there! (That is, there may be xml data, tiffs and/or OG html and images available.) Oh, and another trick to finding which patents are withdrawn is to do a search in patft for ccl/WITHDRAWN, slightly nonsensical syntax but it works!