When an inventor demonstrates his invention to a few friends or associates, the determination of whether such use was public can be difficult. In Moleculon Research Corp. v. CBS, Inc., 793 F.2d 1261 (Fed. Cir. 1986), the inventor displayed a model of his cube puzzle to a few university colleagues. The "personal relationships and surrounding circumstances" were sufficient for the court to find that the inventor had retained control over the invention and the distribution of information concerning it, even though there was no express agreement of confidentiality. Id. at 1266. By contrast, a jury in Beachcombers v. Wildwood Creative Products, Inc., 31 F.3d 1154 (Fed. Cir. 1994) found that a demonstration of an improved kaleidoscope to 20-30 party guests was a public use, and the Federal Circuit affirmed. The purpose of the demonstration was "getting feedback on the device," and the host made no efforts toward secrecy. Id. at 1160.