4.2.2.6.3 C-Sets Syntax Rules

Date Published

Since C-Sets rules are customarily specific to the different technical areas, they vary greatly due to different technical features.

In certain areas, for example, duplicate symbols are allowed in a C-Set, e.g. to reflect the multiple occurrences of a process step corresponding to the repeated CPC symbol.

In other areas, the C-Sets should have exactly one subsequent symbol, e.g. for indicating the combination of a process with a product.

In yet other areas, the C-Sets may have more than one subsequent symbol. In these areas, the order of the symbols may disclose a technical relevance (e.g. B22F2998/10: specific ordered sequence of operations in a multi-step process), or the symbols may be arranged in alphanumerical order (e.g. class C05: specific mixture of compounds in fertilisers).

A CPC patent family may have as many C-Sets as needed to classify all relevant technical features. In addition, further CPC single symbols may be allocated in conjunction with the C-Sets in order to classify any features of interest.

The CPC Definitions provide the C-Sets syntax rules, which are detailed instructions for how to construct C-Sets in the specific technical areas, e.g. to specify the number of symbols in a C-Set; whether duplicate symbols and breakdown codes are allowed or not; the relevance of the order in the string of symbols; and any other special rule relevant for the C-Sets in question.