What are the kind codes for European Patent Office (EPO) publications?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

The European Patent Office (EPO) uses specific kind codes for different types of patent publications. According to MPEP 901.04(a):

“A1” is used for European patent applications published with the European search report.

“A2” is used for European patent applications published without the European search report.

“A3” is used for European search reports published separately from the application.

“B1” is used for European patent specifications (granted patents).

These kind codes help identify the specific type and status of EPO patent documents, which is crucial for patent examiners and researchers when conducting prior art searches.