P owns 4 patents directed to optical information-storage devices, such as compact discs (CDs). D makes CDs. P sued D for patent infringement. The parties stipulated that P's invention date was August 25, 1972. D's defense included that the representative claims were anticipated by an unpatented laser videodisc developed before August 1972 by MCA Discovision, Inc. (MCA). The jury found that all of the representative claims were literally infringed, but that those claims are invalid due to lack of novelty §102(g). P moved for a Judgment as a Matter of Law (JMOL) holding the patents not invalid, or grant a new trial on the lack of novelty issue. P argued that there was insufficient evidence to support the jury's anticipation verdict concerning certain claim limitations. The court noted that the evidence supporting the anticipation finding came from the live testimony of two people who had worked on the MCA laser videodisc project and an expert's report and portions of his deposition testimony, both of which were read into the record, the expert's exhibits, and certain MCA documents that the expert had reviewed. The court held there was substantial evidence that D had shown by clear and convincing evidence that the claims were anticipated by MCA. It denied JMOL. P appealed. P argues that (1) the jury verdict rests upon mere testimonial evidence by the two non-party MCA employees who worked on the videodisc project, and (2) this evidence is insufficient as a matter of law to support a holding of invalidity under subsection 102(g) because such testimonial evidence by inventors of their prior invention requires corroboration.