Why are USPTO and Google Patent Search citation numbers so different?



This (random) patent on Google says it was cited by 67 other patents:


...Same patent on USPTO says it was cited by just 49.


I know that "Cited by Examiner" patents appear in both.

...So what's the difference? Why would Google show more citations than the Patent Office itself?


Posted 2020-02-24T12:47:23.457

Reputation: 1

2After a quick look it seems that the USPTO only identifies granted patents, whereas Google Patents identifies both granted patents and published patent applications. – the Europeist – 2020-02-24T15:57:13.747



The @the Europeist comment is correct - Google is showing references from patent publications. Technically they are not really citations until they appear printed in a patent. It looks like Google is going into PAIR or the Global Dossier to the file wrapper and getting information from the IDS forms filed in the applications.

George White

Posted 2020-02-24T12:47:23.457

Reputation: 21 648


Google patent capture all the patents i.e., US and Non US ( WO,EP,AU ETC.,) Where as USPTO capture only the US data the difference is due to the fact there are other Non US parents present in the Google patent.


Posted 2020-02-24T12:47:23.457

Reputation: 1 279

This is not correct. In the example given in the question there are all US patents and applications except for one PCT application. Separately, if a foreign reference is cited by an examiner in the USPTO it will certainly show up on the face of the patent as a cited document. – George White – 2020-02-28T01:33:46.243