Reconsider the Trade Show: Minerva Surgical v. Hologic and the Public Use Bar for Patents

Have you considered bringing your latest invention to a trade show? If so, the latest Federal Circuit ruling in Minerva Surgical v. Hologic illustrates why you might want to hold off on displaying the invention to the public until you’ve filed a patent application. 

Minerva Surgical and Hologic create devices to treat heavy uterine bleeding. In 2021, they had an intellectual property case reach the Supreme Court (see our related article here) in which the majority upheld the assignor estoppel doctrine, narrowing its scope but still preventing assignors from declaring patents invalid after assignment. However, as any Yankees or Red Sox fan will tell you, a great rivalry doesn’t die overnight. And now, the Federal Circuit has issued the latest ruling in the lengthy legal battle between these two competitors.

In the most recent case, Minerva accused Hologic of infringing on a patented device to assist in surgeries for uterine bleeding. Minerva performed extensive testing on this prototype, called the “Aurora,” before bringing fifteen such devices to a trade show in 2009. At the event, the company displayed the Aurora, pitched the technology to investors, and gave a presentation. At no point did the company require parties to sign confidentiality agreements to see the device. Over a year after the trade show, Minerva filed a patent for the Aurora technology. When Hologic began using a similar technology in its devices, Minerva proceeded to sue its competitor for patent infringement.

Last week, the Federal Circuit released its decision in the case. It ruled that Hologic did not infringe upon Minerva’s patent because as outlined in § 102(a) of the 1952 Patent Act, “[a] person shall be entitled a patent unless . . . the invention was . . . in public use . . . in this country, more than one year prior to the date of the application for patent in the United States,” and Minerva ran afoul of this statute. Courts generally consider an invention to have met the bar for public use if it is:

1) accessible to the public or sold by its inventor and 

2) “ready for patenting,” which means that the technology works for its intended purpose. 

The Federal Circuit determined that Minerva put the Aurora device into public use by displaying it at the trade show. This event—which Aurora inventor Truckai called his industry’s “Super Bowl”—brought the device to the attention of surgeons, investors, and competitors. At the show, Minerva even demonstrated the Aurora, using it to treat heavy bleeding on a uterine model. The court ruled that, with this demonstration, Minerva met both criteria for public use: it made the Aurora accessible to the public and showed that the technology fulfilled its intended purpose. Critically, Minerva also waited over a year to file the patent application, rendering its patent invalid.

The Minerva case reveals the risks of showing off an unpatented product. The next time you consider unveiling a technology at a trade show or big presentation, ask yourself—or even better, your attorney—whether it would trigger public use. There will come a time when it’s safe to share your idea with interested parties, but perhaps file a patent application first. Otherwise, as Minerva exemplifies, you might lose out on the exclusive rights to your invention.