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Last seen: 10/25/2023 - 09:38
Joined: 10/20/2023 - 03:12
USPC to CPC conversion/concordance table


I would like to convert USPC to CPC codes. Is there a resource matching these classification schemes?

In that context: Why is g_uspc_at_issue so much smaller than g_cpc_current?

Best, Valentin

Last seen: 11/16/2023 - 15:24
Joined: 11/14/2017 - 22:15
there is a csv


There is a csv here that may be what you are looking for.  There wasn't a one to one mapping when the USPTO added CPCs to patents though.   There's a lot about it here.  Also, the USPTO stopped assigning USPCs to utility patents after May 2015 so you wouldn't be a able to convert anything issued since then. 

The USPTO's classification timeline shows that the first US patent grant published with CPC symbols was issued in March of 2013.  The at-issue CPCs would only be in the weekly xmls after that while the current CPCs should be present for all utility patents.  I didn't look at both files but that could explain the size difference.  There have been posts about a bad data load so I'm not sure if the bulk files have been reloaded.

The current CPCs are available in bulk for utility patents here and the last bulk USPC file is still in if you want to build your own concordance. The USPTO's current CPC file should match up fairly closely with patentsview's current CPCs though the timings can be different.  patentsview updates about quarterly and the USPTO monthly.

The CPC has changed over time so I don't know if the at-issue CPC values have any real meaning. If you are comparing two patent's at-issue values, they might not have been classified under the same version. 

I hope that helps,
Russ Allen

Role: moderator
Last seen: 11/22/2023 - 13:03
Joined: 10/17/2017 - 10:47
classification file size differences

Hi Valentin, 

Russ has correctly noted that the USPTO discontinued the assignment of USPC codes shortly after it instituted the assignment of CPC codes, and as a result, both USPC-at-issue and CPC-at-issue are smaller than CPC-current due to cpc-current covering all utility patents back to 1976, whereas each at-issue file only covers a subset of the utility patents issued within that date range. We’re happy to confirm that the data load issue that produced incomplete CPC files for a brief period following our data update in September has been resolved, although if you find any continuing issues of data completeness or accuracy, please let us know!