What is the difference between the Brief Summary of Invention and the Detailed Description in a patent application?

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 Brief Summary of Invention and the Detailed Description serve different purposes in a patent application:

• Brief Summary: According to MPEP 608.01(d), it should provide a concise overview of the invention’s nature and substance. The MPEP states, “A brief summary of the invention indicating its nature and substance, which may include a statement of the object of the invention, should precede the detailed description.”
• Detailed Description: This section provides a comprehensive explanation of the invention, including how to make and use it, as required by 35 U.S.C. 112(a).

The Brief Summary is meant to give a quick understanding of the invention, while the Detailed Description provides the full technical disclosure necessary for enablement and written description requirements.