Cracking the number code: Format changes in the EPO Concordance table

Helping you translate data into business insight

The EPO Concordance table is updated weekly and made available to all users via the Bulk Data Distribution Service. It provides a comprehensive reference for interpreting patent bibliographic data, including:

• All publication number formats and kind codes
• All application and priority number formats and kind codes
• The corresponding WIPO ST.30 tag, also called “date of public availability”

The concordance table is generated directly from the business rule engine used by the EPO’s prior-art teams to process bibliographic data, ensuring consistency between internal processing and published datasets.

An extract of the concordance table for United States publications is shown below. For each kind code, the table specifies the associated number format and a description of the corresponding document type.

Update to US A1 number format

Since 2026, new US A1 publications have adopted a new number format to align with the original format used by the United States Patent and Trademark Office (USPTO).

The EPO plans to re-key US A1 documents published before 2026 to the new format between February and March 2026.

Impact on Espacenet searches

To retrieve US documents published after 1.1.2026, you must use the original US format.

Example: US20260019959A1

Keywords: Concordance table, number format, kind code, WIPO ST.30, WIPO ST.16