The United States Court of Appeals for the Federal Circuit held that a patent applicant can invalidate his or her patent by sending certain types of letters prior to the filing date of a patent application. See Junker v. Medical Components, Inc., et al., Appeal No. 2021-1649 (Fed. Cir. February 10, 2022). Specifically, the decision indicates that such letters could contain commercial offers that trigger the on-sale bar, which will render the invention unpatentable.

The two-prong test for the on-sale bar indicates that a patent claim will be invalid when the claimed invention was both (1) the subject of a commercial offer for sale and (2) ready for patenting. Pfaff v. Wells Elecs., Inc., 525 U.S. 55, 67–68 (1998). The issue of the applicability of the on-sale bar is “a question of law based on underlying factual findings.” Meds. Co. v. Hospira, Inc., 827 F.3d 1363, 1371 (Fed. Cir. 2016) (en banc).

The invention-at-issue in Junker was an ornamental design for a medical-device component. Specifically, the device was a handle for introducer sheath. The handle had large, rounded “Mickey-Mouse-shaped ears” that made it easier for doctors to grasp the introducer sheath during catheter-insertion procedures.

The inventor entered into a business relationship with a medical-device company to exploit the invention commercially. That relationship did not trigger the on-sale bar. Rather, a principal for the medical-device company started sending out letters to try attract customers for the device.

The Federal Circuit examined those letters and determined that they constituted commercial offers, not mere invitations to negotiate. The Federal Circuit ended up reversing a district court decision finding for the inventor that there was no on-sale bar.

Consequently, this case demonstrates the need to take considerable care when trying to develop your invention commercially before filing a patent application.