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4 posts
vdacru
Last seen: 07/15/2022 - 08:08
Joined: 04/26/2020 - 02:45
Forward Citations

Dear Patentsview Team

I am working with patent data to analyse state-level patents. Instead of using a simple patent count, I would like to weigh them by forward citations. For this, I need to calculate the number of citations.

I am planning to merge the patent data with the usapplicationcitation by "patent id" and then counting the citations. Or is this incorrect? If so, what would be the best way to go about this? 

Thank you for your help!

Best

Vanessa

Wed, 06/02/2021 - 12:29
PVTeam
Role: moderator
Last seen: 04/23/2024 - 10:43
Joined: 10/17/2017 - 10:47
FORWARD CITATIONS

Hi Vanessa,

Thank you for reaching out to our team!

What you should do depends on what you mean by "I would like to weigh them by forward citations."

A forward citation is any citation made to a published patent document by a patent issued at a later date. For instance, patent 8219438 was published on 2012-07-10 and was later cited by 94 other patents published after this date. Therefore, this patent has been forward cited 106 times.

Using 8219438 as an example again, the method you proposed would instead count the total number of applications cited by 8219438 (10). 

If you are looking to weigh patents by the number of times they themselves have been forward cited, you should download the uspatentcitation table. To determine the number of forward citations for a patent such as 8219438, you would then filter the table by citation_id = 8219438 and count the number of rows returned to get 94. You can do a group-by and count on all the ids in the citation_id column to get the number of forward citations for each patent.

To continue with the method you proposed of counting the number of citations made per patent you should download both the uspatentcitation and the usapplicationcitation tables. You can then do a group-by and count on patent_id to see the total number of citations made by each patent. For 8219438, this would be 20 patents and 10 applications for a total of 30 citations.

Hopefully this helps you get all the data you need! If you have any other questions please let us know.

Best,

PVTeam 

 

Tue, 10/19/2021 - 23:05
leohl
Last seen: 10/20/2021 - 15:15
Joined: 06/26/2021 - 12:23
Dear PVTeam, thanks for the…

Dear PVTeam,

thanks for the previous answer. That already helped a lot.

I have a follow-up question regarding this topic: Are there in the usapplicationcitation file only applications that were never granted? Or does this file also includes applications of subsequently granted patents?

Thank you!

Best regards

Thu, 10/21/2021 - 11:13
Russ
Last seen: 03/21/2024 - 09:05
Joined: 11/14/2017 - 22:15
It's complicated

It's both ones that went on to be granted patents and ones that weren't granted or haven't been granted yet.  Note that date ranges are different. Patent data is available from 1976 on but the application data is only available from 2001 on.  

Part of the patent statute says that an inventor can elect to suppress publication if they are only applying for a patent in the US. https://www.uspto.gov/web/offices/pac/mpep/s1122.html  So you won't necessarily find the application for every patent granted from 2001 on.

You can see this in action if you look at the granted_patent_crosswalk on the pre-grant download page.  It does not have a document_number for every granted patent since 2001 which I assume can be attributed to suppressed applications.

Russ