patent citation (backward citation)

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dvlajcic
Posts: 2
Joined: Thu Sep 13, 2018 9:44 am

patent citation (backward citation)

Post by dvlajcic » Thu Sep 13, 2018 10:06 am

Hi everyone,
I started using PATSTAT very recently and find it very useful. My research interest is basically around technology and knowledge transfer, so I am mostly interested in patent citation data. I am not very familiar with database search (in PATSTAT case SQL), but I am determine to spent as much as time needed to master this skill. However, before I dig into studding, I would like to know whether PATSTAT actually can provide me with needed data or am I on a wrong track.
Here is my research interest:
I have a list of multinational companies. I need all the patents owned by those companies and IPC classification of that patents. Furthermore, for each of that patent I need patents they cited (backward citation) and IPC classification of each of that cited patent.
Hope I made my question clear enough, and someone can give me his opinion on duability of my idea.
Best,
Davor


EPO / PATSTAT Support
Posts: 50
Joined: Thu Feb 22, 2007 5:33 pm

Re: patent citation (backward citation)

Post by EPO / PATSTAT Support » Thu Sep 13, 2018 5:36 pm

Hello Devor,
that is perfectly possible.

Here is a query that does something similar; analyse it and it should be clear what it is doing.
You can of course adapt the criteria to what you need for your research.
To illustrate better what it does, adapt the query to only1 citing application, and then analyse the rows you retrieve. (Maybe by quikly looking up the information in www.espacenet.com, where you will find the ipc codes and the cited documents.)
Your result list will give as many rows as the number of comibinations of IPC classification codes from cited and citing publications. So even with a relative small number of patents, you will have a lot of rows to deal with. Therefore you should limit as much as you can your data set from the onset on.

Code: Select all

SELECT DISTINCT i.ipc_class_symbol cited_IPC ,ii.ipc_class_symbol citing_IPC
, citing.publn_auth + citing.publn_nr
, cited.publn_auth +cited.publn_nr
, citeda.appln_filing_year
, citeda.granted
, j.citn_origin
,psn_name
FROM tls211_pat_publn as citing 
JOIN tls212_citation as j ON citing.pat_publn_id = j.pat_publn_id
JOIN tls211_pat_publn AS cited ON j.cited_pat_publn_id = cited.pat_publn_id
JOIN tls209_appln_ipc as ii on citing.appln_id=ii.appln_id
JOIN tls209_appln_ipc as i on cited.appln_id=i.appln_id
JOIN tls201_appln as citinga on citing.appln_id=citinga.appln_id
JOIN tls201_appln as citeda on cited.appln_id=citeda.appln_id
JOIN tls207_pers_appln on tls207_pers_appln.appln_id = citinga.appln_id
JOIN tls206_person on tls207_pers_appln.person_id = tls206_person.person_id
WHERE psn_name = 'VESTAS'
AND
((i.ipc_class_symbol LIKE 'F03D%'
AND DATEDIFF (day, cited.publn_date, citing.publn_date) < 1825
AND citeda.docdb_family_id<>citinga.docdb_family_id
AND j.citn_origin <>  'app'
AND citeda.appln_id = citeda.earliest_filing_id
AND citeda.appln_auth='CN')

OR 

(i.ipc_class_symbol LIKE 'F03D%'
AND DATEDIFF (day, cited.publn_date, citing.publn_date) < 1825
AND citeda.docdb_family_id<>citinga.docdb_family_id
AND j.citn_origin <>  'app'
AND citeda.receiving_office='CN'))
order by  citing.publn_auth + citing.publn_nr
PATSTAT Support Team
EPO - Vienna
patstat @ epo.org


dvlajcic
Posts: 2
Joined: Thu Sep 13, 2018 9:44 am

Re: patent citation (backward citation)

Post by dvlajcic » Mon Oct 08, 2018 9:08 am

Hi again,

first of all, i would like to thank you for suggested query. I studied it in detail and I can say that this query could gave me information needed. However, I would need is an advice from you.
Most of the research focused on knowledge transfer, uses patent families instead of individual patents filed in specific country. It is a bit confusing for me whether your query refers on patent families or on patent filled in specific country (in your case CN - China)? I think that with focusing on patent families, and families which are citing them we could avoid repeating of same publication in different countries and by that we could decrease number of observation (since my focus in not specific country, but specific MNC operating world-wide)

I would really appreciate help with this query.
Thank you up front,

Best,
Davor


EPO / PATSTAT Support
Posts: 50
Joined: Thu Feb 22, 2007 5:33 pm

Re: patent citation (backward citation)

Post by EPO / PATSTAT Support » Tue Oct 09, 2018 9:24 am

Hello Devor,
your observation is correct, but if you do a family-family analysis, then you have to give your data preparation a serious thought on what attributes you will migrate to family level, and more important how you will do that for attributes that are "application" bound. Very specific: how would you deal with different classifications, (possible different) applicants and different GRANT statuses ?
Adding the DocDB family identifier is of course not a problem.

Code: Select all

SELECT DISTINCT i.ipc_class_symbol cited_IPC ,ii.ipc_class_symbol citing_IPC
, citing.publn_auth + citing.publn_nr
,citinga.docdb_family_id
, cited.publn_auth +cited.publn_nr
,citeda.docdb_family_id
, citeda.appln_filing_year
, citeda.granted
, j.citn_origin
,psn_name
FROM tls211_pat_publn as citing 
JOIN tls212_citation as j ON citing.pat_publn_id = j.pat_publn_id
JOIN tls211_pat_publn AS cited ON j.cited_pat_publn_id = cited.pat_publn_id
JOIN tls209_appln_ipc as ii on citing.appln_id=ii.appln_id
JOIN tls209_appln_ipc as i on cited.appln_id=i.appln_id
JOIN tls201_appln as citinga on citing.appln_id=citinga.appln_id
JOIN tls201_appln as citeda on cited.appln_id=citeda.appln_id
JOIN tls207_pers_appln on tls207_pers_appln.appln_id = citinga.appln_id
JOIN tls206_person on tls207_pers_appln.person_id = tls206_person.person_id
WHERE psn_name = 'VESTAS'
AND
((i.ipc_class_symbol LIKE 'F03D%'
AND DATEDIFF (day, cited.publn_date, citing.publn_date) < 1825
AND citeda.docdb_family_id<>citinga.docdb_family_id
AND j.citn_origin <>  'app'
AND citeda.appln_id = citeda.earliest_filing_id
AND citeda.appln_auth='CN')

OR 

(i.ipc_class_symbol LIKE 'F03D%'
AND DATEDIFF (day, cited.publn_date, citing.publn_date) < 1825
AND citeda.docdb_family_id<>citinga.docdb_family_id
AND j.citn_origin <>  'app'
AND citeda.receiving_office='CN'))
order by  citing.publn_auth + citing.publn_nr
PATSTAT Support Team
EPO - Vienna
patstat @ epo.org


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