What is the role of drawings in satisfying the written description requirement?

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.

Drawings can play a crucial role in satisfying the written description requirement. The MPEP states:

“An applicant may show that the inventor was in possession of an invention by disclosure of drawings or structural chemical formulas that are sufficiently detailed to show that the inventor was in possession of the claimed invention as a whole.”

Key points about drawings and written description:

• Drawings alone may provide sufficient written description in some cases.
• The level of detail in the drawings should show possession of the claimed invention.
• For chemical inventions, structural formulas can be particularly important.
• Drawings can help “flesh out” words in the specification to provide adequate written description.

However, the adequacy of the drawings in meeting the written description requirement depends on the nature of the invention and the level of detail provided.