premise: Nothing disclosed under this Agreement is considered Proprietary Information unless  (a) it is received in a tangible form and is marked “confidential” or “proprietary”,  (b) is received in intangible form and is followed up within a reasonable period of time with a writing describing it and designating it as “confidential” or “proprietary”, or  (c) it is something by either the substance of which or the circumstances surrounding its disclosure would lead a reasonable person to believe it is confidential or proprietary.