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https://www.ipo.gov.uk/p-ipsum.htm
Classification1, preclassification2 (if applicable), reclassification3 activities; classification systems used (e.g., International Patent Classification (IPC)); matters concerning indexing of patent information
All UK patent applications are classified in the IPC. In 2005 the IPO started classifying all UK patent applications in ECLA, which was replaced by CPC classification in October 2013. Pre-classification (i.e. allocation of applications to examining groups) is done manually at subclass level using the CPC. Clusters of CPC subclasses provide the basis for the structure of examining divisions and groups. The office does not reclassify documentation.
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