Anticipation Under the Public Use Bar

April 4, 2023

Minerva Surgical, Inc. sued Hologic, Inc. and Cytyc Surgical Products, LLC in the District of Delaware for infringement of U.S. Patent No. 9,186,208. After discovery, the district court granted summary judgment that the asserted claims were anticipated under the public use bar of pre-AIA 35 U.S.C. § 102(b). Minerva appealed. The Court of Appeals for the Federal Circuit (the Court) affirmed.

The Court agreed that the patented technology was “in public use” because, before the critical date, Minerva disclosed fifteen devices having the patented technology at a public event, the industry’s “Super Bowl.” Minerva’s disclosure of these devices spanned several days and included Minerva showcasing them at a booth, in meetings with interested parties, and in a technical presentation. Minerva did not disclose the devices under any confidentiality obligations, despite the commercial nature of the event. Also, at the time of the public use, the technology was “ready for patenting,” as Minerva had created working prototypes and enabling technical documents describing the claimed technology.

The ’208 patent is directed to surgical devices for endometrial ablation, which stops or reduces abnormal uterine bleeding. Representative claim 13 recites:

            13. A system for endometrial ablation comprising:
            an elongated shaft with a working end having an axis and comprising a compliant energy-delivery surface actuatable by an interior expandable-contractable frame;
            the surface expandable to a selected planar triangular shape configured for deployment to engage the walls of a patient’s uterine cavity;
            wherein the frame has flexible outer elements in lateral contact with the compliant surface and flexible inner elements not in said lateral contact, wherein the inner and outer elements have substantially dissimilar material properties.

The appeal focused on the claim term “the inner and outer elements have substantially dissimilar material properties” (“SDMP” term), which was construed by the court to mean that the “inner and outer frame elements have different thickness and different composition.” According to Hologic, on November 16–19, 2009, more than a year before the ’208 patent’s priority date, Minerva brought a device called “Aurora” to the 38th Global Congress of Minimally Invasive Gynecology (“AAGL 2009”) and argued that the Aurora device disclosed every limitation of the asserted claims and that the asserted claims were therefore invalid as anticipated by Minerva’s own device.

Minerva began the development of the Aurora device in 2008. By early 2009, Minerva had begun developing prototypes, but they lacked a frame, an “inner flexure,” “lateral symmetry,” and the SDMP technology. By mid-2009, Minerva had prototypes that could be inserted into uteri, could deliver energy necessary to perform the surgery, and could be withdrawn after the procedure, but the prototypes’ frames were “deforming too much.” In July 2009, Minerva began testing the Aurora device on surgically-removed human uteri. A report analyzing the tests conducted on October 1 and November 14, 2009, describes that all Minerva devices were successfully deployed and conformed to the uterus, and the devices were removed successfully post-ablation. These results align with the benefits that the SDMP technology is intended to achieve. The report concluded that “the Minerva device would be considered acceptable for clinical use in pre-hysterectomy cases.” The inventor also confirmed that the important elements of the system were known to Minerva by August 2009. Minerva’s R&D prepared 15 fully functional devices ready to bring to AAGL 2009, where Minerva obtained a booth to demonstrate the Aurora devices.

Minerva gave a presentation at AAGL 2009 discussing the Aurora device. A brochure, distributed at AAGL 2009, explained that the presentation would include discussion of “[t]he disposable device’s ability to conform to the uterus [to] enable treatment of uterine cavities with deformities and variable volumes.” An “Investigator’s Brochure” dated November 20, 2009, provided a detailed description of the Aurora device and identified that its frame elements were made of “Stainless steel (420 and 17-4),” which is consistent with the August 2009 CAD drawings. Similarly, a Bill of Materials from November 24, 2009, lists the same frame elements. These documents disclose the SDMP term. The inventor also testified that the device referenced in the Bill of Materials was likely the Aurora device shown at AAGL 2009. In view of the record, the district court granted summary judgment that the asserted claims were anticipated under the public use bar. Minerva appealed.

The “in public use” element of the bar is met if the invention was accessible to the public or was commercially exploited by the inventor. “Ready for patenting” - the second element of the public use bar - may be shown by proof of reduction to practice before the critical date or by proof that prior to the critical date the inventor had prepared drawings or other descriptions of the invention that were sufficiently specific to enable a person skilled in the art to practice the invention.

In Public Use. The Court agreed that “the nature of and public access to activities involving” the Aurora device at AAGL 2009 indicated public use. AAGL 2009 was the “Super Bowl” of the industry and was open to the public. It included attendees who were critical to Minerva’s business, potential investors and physicians, and Minerva had every incentive to showcase the Aurora devices to the attendees. Minerva brought 15 fully functional Aurora devices and the disclosure of these devices spanned several days and included Minerva showcasing them at a booth, in meetings with interested parties, and in a technical presentation.

Minerva argued that its “mere display” of the Aurora device at AAGL 2009 did not rise to the level of “public use.” The Court disagreed, as Minerva pitched the Aurora device to various sophisticated industry members, who were allowed to scrutinize the Aurora device closely and see how it operated. The Court further noted that “public use may also occur where, as here, the inventor used the device such that at least one member of the public without any secrecy obligations understood the invention.” Minerva allowed knowledgeable individuals to scrutinize the invention enough to recognize and understand the SDMP technology Minerva later sought to patent. There were no “confidentiality obligations imposed upon” those who observed the Aurora device.

Ready for Patenting. The Court concluded that the district court correctly determined that the Aurora device was ready for patenting, because Minerva reduced the invention to practice and had enabling documentation describing the invention of claim 13. Minerva reduced the invention to practice by creating working prototypes that embodied claim 13 and worked for the intended purpose of performing endometrial ablations. The evidence establishing this included inventor’s testimony explaining the prototypes and their implementation of the SDMP technology, the extirpated uteri studies, and the documents describing the prototypes.

Minerva further insisted that the Aurora device did not function for its intended purpose of performing ablations on “live human” uteri and therefore there was a factual dispute as to reduction to practice. The Court explained that case law did not require imposing the “live human” requirement here and noted that the extirpated uteri studies concluded that the Minerva device would be considered acceptable for clinical use in pre-hysterectomy cases, “in other words that the Aurora device would be considered acceptable for use in clinical trials on live humans.” The court pointed out that even the inventor testified that the disclosed versions of the Aurora device were nearly “perfect.”

The Court further explained that the invention was ready for patenting as there was documentation “sufficiently specific to enable a person skilled in the art to practice the invention” of the disputed SDMP term of claim 13. The documents included drawings and detailed descriptions in the 2009 lab notebook pages disclosing a device with the SDMP term. The Court agreed with the district court that there was no genuine issue of material fact that the invention of claim 13 was “ready for patenting” before the critical date of the ’208 patent. The Court concluded that Minerva’s disclosure of the Aurora device constituted the invention being “in public use” and that the device was “ready for patenting” and affirmed the district court’s grant of summary judgment.

This case is a reminder that showing your device until you have filed a patent application may have detrimental consequences under the public use bar. 

Minerva Surgical, Inc. v. Hologic, Inc., Case No. 2021-2246 (Fed. Cir. Feb. 15, 2023)