What's new with the classification of INPADOC legal events?

11 October 2021

With about 350 million legal event records, the INPADOC database is a data pool that requires a classification scheme to make it easier to understand and retrieve relevant records.

The EPO is taking the necessary steps under standard ST.27, published by the World Intellectual Property Organization, to implement a scheme for classifying each legal event on different levels. (Note that classification in this context should not be confused with patent classification schemes such as IPC or CPC.)

As mentioned in a previous Patent Information News article, phase I involved classifying about 3 000 events at category level (A to Z). Information on the categories and further details on legal event classification can be found in standard ST.27. Over recent months, the EPO has been busy implementing phase II – classification at detailed level.

What's the difference between ST.27 and the INPADOC classification scheme?

The scheme used at the EPO is largely aligned with ST.27, but not entirely.

Unlike ST.27, category G in INPADOC, which covers term extensions in general, also contains events related to supplementary protection certificates in order to separate them from patent applications classified in other categories.
In addition, the INPADOC classification scheme generally includes information on events related to procedural steps that did not occur, assigning them to the category covering the related positive event. For example, the related positive event for "non-entry into the national phase" is "entry into the national phase", which is covered in category A (Application filing). Accordingly, "non-entry into the national phase" is also covered in category A.

The INPADOC classification system does not include category N (Termination) used in ST.27 because category N is only intended for the definitive termination of an application or IP right. However, as remedies against termination are generally available, it does not seem appropriate to use this category in the INPADOC classification.


The detailed code as laid out in the INPADOC classification scheme uses three elements: category, sub-category and procedural step. For an event with the description "Filing of a supplementary protection certificate", the detailed code is G10A:

Category: Protection beyond IP right term – G
Sub-category: Supplementary protection certificate – 10
Procedural step: Application filed – A

Current progress

Phase II – classification at detailed level – has now been finalised for 11 categories, with more to follow in 2021. The scheme used at the EPO is still being fine-tuned to ensure it is fit for purpose, so the results will not be published until the classification scheme is fully set up. In a first step, the classes will be made available in the weekly statistics table displaying the INPADOC coverage. In a second step, the data will then be made available in the INPADOC xml product and in other services.

Espacenet and the Global Patent Index already show the categories for legal events in the INPADOC data, and searches can be conducted in Global Patent Index on the basis of those categories.

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