Level 3 and Level 6 in CPC ancestors

Here you can find announcements regarding the EPO's patent information products and services, events and activities.

Please also feel free to ask questions and share information on general patent information matters.
Post Reply

Posts: 3
Joined: Thu Nov 16, 2017 6:42 pm

Level 3 and Level 6 in CPC ancestors

Post by shahzeb_akhtar » Thu Nov 16, 2017 6:55 pm


When using a query like - http://ops.epo.org/rest-services/classi ... &ancestors to get the ancestors of a CPC code, the information in Level 3 and Level 6 seems to be incorrect. For example in the above query for code "H04L2012/2841" - Level 3 symbol is "H01" and Level 6 symbol is "H04L1/00". Both of them dont seem to be the ancestor for the queried code.

My questions are:
1. What do level 3 and 6 signify. Like level 2 is Section, Level 4 is Class and so on in the CPC heirarchy.
2. Is it safe to just always ignore Level 3 and 6 in response to a http://ops.epo.org/rest-services/classification/cpc/ query? Can there be other levels I need to verify/check in the response?


EPO / OPS Support
Posts: 999
Joined: Thu Feb 22, 2007 5:32 pm

Re: Level 3 and Level 6 in CPC ancestors

Post by EPO / OPS Support » Wed Feb 14, 2018 2:36 pm

Dear user

Thank you for informing us about ancestor display issue - we have contacted the department in charge and they will have a look at it and will make appropriate corrections if necessary.

As far as your first question, here are descriptions of individual levels:
Level=1 is root
Level=2 is section
Level=3 is subsection (subsection is analogue to a guidance heading and in fact not part of classification hierarchy, which I believe answers part of the question below)
Level=4 is class
Level=5 is subclass
Level=6 is guidance heading (not part of the classification hierarchy)
Level=7 is main group
Level=8 is a 1-dot level subgroup
Level=9 is 2-dot level subgroup
And so on....

We cannot reply to your second question because it really depends on what you need as far as information given. Maybe it will be better to wait with this decision until the CPC department makes corrections in the hierarchy. I will post another reply once they have a chance to look at your issue and make changes.

In the future, you are welcome to post OPS-related topics into OPS Forum too.

OPS support

Post Reply