https://www.epo.org/en/searching-for-patents/helpful-resources/patent-knowledge-news/cpcs-searchable-ep-document

CPCs searchable on EP document publication date

CPCs assigned by EPO examiners to EP applications are searchable on or after week 37 2021 (publication date 15 September 2021) in a number of EPO tools, including the European Publication Server.

In the following example we enter CPC Y02P20 in the IPC/CPC field and select kind code A1 to retrieve all A1 documents published by the EPO on or after 15 September 2021 in the field of climate change mitigation technologies relating to the chemical industry.

If we click the XML link beside a publication number in the hit list, a view of that individual publication is displayed - in this case EP3889128A1. Under the list of IPC symbols, a number of CPC symbols are indicated, including the one we used in our search. Note: CPC information is not yet available in the official PDF version of EP publications.

In the above publication we can also see two Combination Sets - or "C‑Sets" - below the CPC symbols. Unlike individual CPC symbols that classify a specific technical feature, linked symbols - also assigned by patent examiners - classify technical features "taken in combination" and vary in meaning depending on the technical field.
A C-Set

  • can be thought of as a recipe featuring a sequence of ingredients (CPC symbols)
  • can link chemical compounds and processes, as in our example
  • can have multiple layers, each layer being a separate C‑Set.

Visit the CPC Training webpage for more information on C‑Sets.

In addition to their searchability in the European Publication Server, CPCs and C‑Sets are also searchable from the EP publication date in the following tools:

EP full-text search

EP Bulletin search

At global level, CPC and C-Sets are also searchable in:

Espacenet

Global Patent Index (GPI)

PATSTAT Online

The following is an example of a GPI document showing classification information, including "CPC International" information where all CPC symbols assigned by CPC-classifying offices are aggregated and propagated to all members of a given simple patent family.