INID Codes (how to read a patent)

The different bibliographic data on the front page of a patent document can be identified by the help of two-digit numbers (INID codes) placed within parentheses, brackets or circles in front of the relevant data element.

INID codes are a two-digit standard list of Internationally agreed Numbers for the Identification of (bibliographic) Data on patents. Below is a list of some of the most frequently used INID codes, see also the front-page images:

The INIC codes help to find standardised patent document related information (e.g. like the inventor) independently of the language or structure of the document - see e.g. a European, German, US and Chinese patent document below: