When does experimental use end in patent law?

Experimental use ends when the invention is actually reduced to practice. The MPEP states: “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))

Once the inventor is satisfied that the invention is complete and functional for its intended purpose, any further activity is generally not considered experimental use. This is true even if the inventor is awaiting approval from external organizations or making minor refinements that are not claimed in the patent application.

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