Following our representations, IPOS has confirmed the new format for application numbers of registrable IP  (e.g., trade marks, patents, registered designs) filed on or after 14 February 2014.

The new application number format will not use alphabetic identifiers, but rather numeric identifiers.

This is the first time that IPOS has released details of the algorithm they use to calculate the check digit. They did so on our representations that the widespread availability of the algorithm is in the public interest.

Application Number Format

IPOS has confirmed that the format for application numbers will be in the form



AA is the type of IP

YYYY is a four digit year

NNNNN  is a five digit serial number, padded with 0s, which is reset to 00000 every year

C is a check digit (P, Q, R, S, T, U, V, W, X or Y)

DD appears to be a two digit extension (serial number, padded with 0s) to indicate a trade mark divisional application

IP Type Code

  • 10 for domestic patent applications

  • 11 for national phase patent applications

  • 30 for registered design applications

  • 40 for trade mark applications

Note for the curious and observant: is the IP type code “20” being reserved for some other type of registrable IP, and if so, what? Utility models would be my first guess…

Check Digit

The check digit is calculated using the Damm algorithm:


102013000005P - patent application, filed as a domestic patent application

40201300054R-01 - trade mark divisional application

Current Application Number Format

The algorithm for calculating the check digit for the current application number format (YYYYNNNNN-C) has (to our knowledge) not been made publicly available, but it is not difficult to reverse engineer.

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