Cooperative Patent Classification (CPC) in IFI CLAIMS Direct

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The Cooperative Patent Classification (CPC) is a new patent classification system developed jointly by the United States Patent and Trade Mark Office (USPTO) and the European Patent Office (EPO). CPC will be launched in January 2013 and will replace national patent classifications currently used at the EPO (ECLA and ICO) and at the USPTO (USPC) after a transition period. Below you can find some useful information on the implementation of CPC in IFI CLAIMS Global Patent Database.


CPC Scheme

The CPC scheme consists of about 250,000 subdivisions and is mostly based on the ECLA scheme currently used at the EPO. In addition to ECLA groups, the CPC scheme also includes:

  • all former EPO ICO codes
  • most of the former EPO-controlled keywords
  • some entries derived from USPC such as subdivisions of Business methods
  • some USPC special collections and digests
  • Y section of ICO

Format of CPC symbols
Initially CPC symbols keep the same digits after the "/" as their parent IPC symbols. CPC subdivisions that do not exist in the IPC are based on ECLA. The alphanumeric symbols existing after the "/" in ECLA are converted into purely numeric symbols. The resulting CPC format aligns with WIPO's specifications for IPC.

Example of conversion:

H01L21/027 H01L21/027 H01L21/027
  H01L21/027B6 H01L21/02727
  H01L21/027B6B H01L21/02736
  H01L21/027B6B2 H01L21/02745

You can find the complete CPC scheme here:

Only textual changes are expected to be made to this initial version of the CPC scheme before the full CPC implementation on 1 January 2013.


CPC implementation at Patent Offices

Implementation at the EPO
From January 2013 the EPO will classify its documents using the CPC. The CPC symbols will not be included in the printed documents but in the raw data and in Espacenet. In addition the EPO will assign CPC codes to PCT publications when the EPO is the searching authority and also to PCT minimum documentation, although some delay is expected in this case.

Implementation at the USPTO
The USPTO will have a transition period through the end of 2014. During this transition period new US applications will be classified both in USPC and CPC. Granted patents will be classified either in USPC or in USPC and CPC. From January 2015 the USPTO will classify exclusively in CPC except for plants and designs.

Implementation at other National Offices
CPC is available for use by other IP offices. Currently ES, FI, GB and SE are already using the new classification scheme.

CPC in raw data products distributed by the EPO
The EPO has just delivered a DOCDB backfile that covers ECLA and ICO classes next to the corresponding CPC symbols for the complete collection. Until the end of 2012 the weekly DOCDB deliveries will provide CPC and also ECLA and ICO symbols. From January 2013 onwards the weekly deliveries will only contain CPC and CPCNO.

The EPO has already classified the vast majority of US documents into ECLA. These ECLA classification symbols will be converted into CPC symbols. The offices are making a coordinated effort to classify into CPC the remaining US documents that are not already classified into ECLA.

Harmonized classification practices
A quality assurance system will be put in place to ensure that the classification symbols allocated by both offices are in accordance with the rules for classification compiled in the CPC scheme and the CPC definitions. The EPO will continue classifying US documents into CPC for a transition period until the way both offices use CPC is completely harmonized.

CPC Revisions
The exact frequency of revisions is not yet known, but it is likely that there will be multiple revisions per year. Each revision will have a version date.


CPC in IFI CLAIMS Global Patent Database

General considerations
In addition to the new CPC codes, the IFI CLAIMS Global Patent Database will keep the latest ECLA and ICO symbols assigned to each record. Although they are static values, they may be useful for some specific searches as well as for historical reasons.

You can download the complete new schema and DTD version 1.6 in our customer portal. Remember that access to the customer portal requires registration. If this is a problem for you please contact us.

The EPO announced that the ST-8 attribute to identify "first/later" information on CPCs will only be supported in backfile and frontfile from January 2013 onwards. We will update user documentation as soon as we have more information about this new addition. In any case this will not require any change in the DTD, however it will require reloading some data.

Example CPC XML format
    <classification-cpc  load-source="docdb" scheme="CPC">A47J  43/0716      20130101  I20130101BHEP</classification-cpc>   
    <classification-cpc  load-source="docdb" scheme="CPC">A47J  31/4485      20130101  A20130101BHEP</classification-cpc>   
    <classification-cpc  load-source="docdb" scheme="CPCNO">A47J  43/0716      20130101  I20130101BHGB</classification-cpc>

Scheme attribute
There are two schemes related to the new classification:

  • CPC corresponds to classification symbols from generating office EPO or USPTO
  • CPCNO are CPC symbols allocated by other National Offices

Load-source attribute
This is the source of the raw data that provided us with the CPC content. Two values are allowed: docdb (from the EPO) and patent office (from the USPTO).

In general, when we get the same data from different sources we define preferences to prevent duplicate content. CPC will be an exception at least until the harmonization period finishes. Until then you will get CPC values from both DOCDB and the USPTO in the same record. This data may include same CPC symbols or not.

CPC symbol and related data

Element Position in WIPO/ST.8 Description Values
classification symbol 1 section A,…,H and Y
  2,3 class 01,…, 99
  4 subclass A,…, Z
  5 to 8 main group 1,…, 9999 right aligned
  9 separator /
  10 to 15 subgroup 00,…, 999999
scheme date 20 to 27 version indicator YYYYMMDD
classification value 30 inventive (equivalent to ECLA)
additional (equivalent to ICO or EPO keywords)
action date 31 to 38 date indicating when the code was assigned YYYYMMDD
classification status 39 original
data source 40 human
generating office 41,42 country code only for CPCNO



Timeline for the implementation of CPC
IFI CLAIMS is ready for the CPC launch in January 2013 in terms of DTD and schema changes.
We are already processing the DOCDB backfile.  Due to the large volume of updates we are spreading the CPC data loads over a number of weeks in order to prevent any delays in regular weekly national publications.

The CPC back file data will start to be included in the normal updates shortly.

A new SOLR field will be available as soon as CPC is delivered to CLAIMS Direct instances.
The CPC field will include both schemes CPC and CPCNO. Index patterns will be the same that the current IPC SOLR index.

More information

You can find additional information on the CPC at

For more information, please contact us at