What factors indicate an experimental purpose in patent law?

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 MPEP outlines several factors that courts consider in determining whether a claimed invention was offered for sale primarily for experimental purposes:

• Necessity for public testing
• Inventor’s control over the experiment
• Nature of the invention
• Length of the test period
• Whether payment was made
• Presence of a secrecy obligation
• Record-keeping of the experiment
• Who conducted the experiment
• Degree of commercial exploitation during testing
• Whether the invention requires evaluation under actual conditions of use
• Systematic performance of testing
• Continuous monitoring by the inventor
• Nature of contacts with potential customers

As stated in the MPEP, “Another critical attribute of experimentation is the ‘customer’s awareness of the purported testing in the context of a sale.’” (MPEP 2133.03(e)(4))