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Last seen: 02/28/2024 - 19:35
Joined: 11/14/2022 - 02:14
Y02 Allocation

Hey All,

I am studying the use of YO2 technology classification by the CPC at the USPTO and EPO and am interested in understanding how they allocate a patent as belonging to one of the YO2 classes. The EPO gives the following information 

"The inventories of the Y tags are updated by running search algorithms designed by expert examiners and relying on other CPC symbols, IPC symbols and keywords."

I was just wondering if anyone in this online community had access to more specific information on how this is done? Especially the idea of using keywords.

Thank you!


Role: moderator
Last seen: 03/15/2024 - 15:25
Joined: 10/17/2017 - 10:47
Y02 classification process

Hi Joe

We've identified two papers that may offer some more details on the process:

A new EPO classification scheme for climate change mitigation technologies (Veefkind, Hurtado-Albir, Angelucci, Karachalios & Thumm, 2012)

Supporting global initiatives on climate change: The EPO's “Y02-Y04S” tagging scheme (Angelucci, Hurtado-Albir & Volpe, 2018)


To briefly summarize the descriptions from these papers, the expert examiners mentioned on the EPO page you reference personally developed the text search parameters relying primarily on CPC and IPC codes, and taking into account keywords in abstract text and claims text when necessary. The examiners were tasked with designing the search conditions to satisfy a maximum error rate, and continue to be tasked with updating these search conditions while maintaining this quality threshold when updates to the classification occur over time. The specific keywords were not provided, possibly because they may change over time with updates to the classification scheme.