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Federal Circuit holds surgical patent anticipated under Pre-AIA 35 U.S.C. § 102(b) public use

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

Procedural History

This is an appeal from a District of Delaware summary judgment order that held that the asserted claims of U.S. Patent No. 9,186,208 (the ’208 Patent) are anticipated under the public use bar of pre-AIA 35 U.S.C. § 102(b).  (Slip Op. at 2.)


The ’208 Patent claims a surgical device for endometrial ablation, a procedure which stops or reduces abnormal uterine bleeding. Claim 13 of the ’208 Patent recites, among other things, that the patented device has a frame comprising of inner and outer elements that have substantially dissimilar material properties (“SDMP”). Minerva Surgical, Inc. (Minerva) sued Hologic, Inc. and Cytyc Surgical Products, LLC (collectively “Hologic”) for patent infringement in 2017. (Slip Op. at 5.) Hologic moved for summary judgment of invalidity, arguing that the asserted claims were anticipated under the public use bar of pre-AIA 35 U.S.C. § 102(b).  (Slip Op. at 5.)  Hologic contended that Minerva displayed at an industry conference a prototype of its “Aurora” device which disclosed every limitation of the asserted claims of the ’208 Patent, more than a year before its priority date, thus anticipating the claims under the public use bar of § 102(b). (Slip Op. at 5.)  The district court agreed, and granted summary judgment of invalidity. Minerva Surgical, Inc. v. Hologic, Inc., 550 F. Supp. 3d 158, 169-70 (D. Del. 2021).

On appeal, Minerva raised three main arguments. (Slip Op. at 11). First, relying on Motionless Keyboard Co. v. Microsoft Corp., 486 F.3d 1376 (Fed. Cir. 2007), Minerva argued that the disclosure of the Aurora prototype at the conference was not public use of the device because it was “merely displayed”, not physically handled. (Slip Op. at 11-14.)  Second, Minerva argued that the Aurora prototype lacked the “SDMP term” of claim 13 and therefore, there was no disclosure of that term. (Slip Op. at 11.) Third, Minerva argued that the invention was not “ready for patenting” at the time of the disclosure because Minerva was still improving the SDMP technology such that the Aurora device did not function for its intended purpose of ablating live human tissue. (Slip Op. at 11.)  


The Federal Circuit affirmed the district court’s decision. First, the Court found that Minerva’s disclosure at the conference went beyond “mere display” because, for example, “various sophisticated industry members, [] were allowed to scrutinize the Aurora device closely and see how it operated.”  (Slip Op. at 12.)  Further, the Court found that there were no confidentiality obligations imposed on those observing the Aurora device (e.g., signing an NDA or tightly controlling access). (Slip Op. at 14.) Second, the Court found that the Aurora prototype did in fact disclose the SDMP term of claim 13. (Slip Op. at 15). Third, the Court concluded that the device met the “ready for patenting” requirement because it had been reduced to practice and that Minerva had enabling documentation describing the invention of claim 13. (Slip Op. at 16.) The Court rejected Minerva’s argument that proof the invention could work on “live human” uteri was required to meet this element given that (a) the patent claims were not limited to use on live human tissue and (b) imposing such a standard would be tantamount to requiring FDA approval, which the Court had rejected in prior decisions (e.g., Helsinn Healthcare v. Teva Pharm. USA, Inc., 855 F.3d 1356, 1372-73 (Fed. Cir. 2017).


Key Takeaways

  1. Inventors displaying their unpatented inventions in public forums should carefully consider what confidentiality obligations are in place before providing access to their unpatented inventions.
  2. Inventors who have reached an advanced state of development (e.g., prototypes, etc.) should be aware of the “ready for patenting” threshold, and determine whether their invention meets the criteria before making them broadly accessible.
  3. The Federal Circuit does not require FDA approval or approvability for medical devices to prove that a claimed invention was adequately enabled and ready for patenting.