Can third-party activities qualify as experimental use 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.

Experimental use is personal to the inventor and generally does not extend to independent third-party activities. The MPEP states: “Where an inventor presents evidence of experimental activity by such other party, the evidence will not overcome the prima facie case of unpatentability based upon the activity of such party unless the activity was under the supervision and control of the inventor.” (MPEP 2133.03(e)(7))

This means that for third-party activities to qualify as experimental use, the inventor must maintain supervision and control over the experimentation. Without such control, the activities of independent third parties cannot be used to claim experimental use and avoid statutory bars.