IOENGINE is challenging a jury verdict from the District of Delaware that found certain claims of IOENGINE's patents related to portable devices invalid based on prior art. Specifically, IOENGINE appeals the finding that the DiskOnKey System, including its Firmware Upgrader, was in public use before the invention date, which invalidates their patents. IOENGINE also contested the district court's jury instructions and the allowance of certain prior art at trial. The court affirms the district court's decision, concluding that substantial evidence supported the jury's finding of public use and that the jury instructions were proper. The court also clarifies that Inter Partes Review (IPR) estoppel does not prevent a party from asserting invalidity grounds in district court based on prior art that could not have been raised in the IPR proceeding, such as public use or on sale grounds.  Written case summary here: https://www.cafcnewsbriefs.com/post/ioengine-v-ingenico-decided-may-7-2025