The parties have not addressed the standard of proof Downey must satisfy, specifically, whether the existence of the alleged oral contract must be established by a preponderance of the evidence or by the more stringent standard requiring "clear and precise" evidence. See, e.g.,Park v. Ahn , No. 15-678, 2018 WL 3031851, at *4-6 (W.D. Pa. Jun. 19, 2018) (collecting cases and discussing standard of proof necessary to show existence of oral contract); Fish Net, Inc. v. ProfitCenter Software, Inc. , No. 09-5466, 2013 WL 5635992, at *4 (E.D. Pa. Oct. 15, 2013) (same). The Pennsylvania Supreme Court has held that an "oral contract which modifies or changes or cancels a prior written contract must be proved by evidence which is clear, precise and convincing."