When does experimental use of an invention end?

Experimental use of an invention ends when the invention is actually reduced to practice. According to the MPEP, Experimental use “means perfecting or completing an invention to the point of determining that it will work for its intended purpose.” Therefore, experimental use “ends with an actual reduction to practice.” (MPEP 2133.03(e)(3))

This means that once an inventor has determined that the invention works as intended, any further use or testing is no longer considered experimental use.

To learn more:

• experimental use
• reduction to practice
• patent law
• invention completion