subject matter pertains.” See DyStar Textilfarben GmbH & Co. v. C.H. Patrick Co., 464 F.3d 1356, 1360 (Fed.Cir.2006). As with anticipation, the party challenging the validity of the patent bears the burden of establishing obviousness by clear and convincing evidence. PharmaStem Therapeutics, Inc. v. Viacell, Inc., 491 F.3d 1342, 1360 (Fed.Cir.2007). Obviousness is a question of law based on underlying questions of fact. Daiichi Sankyo Co., Ltd. v. Apotex, Inc., 501 F.3d 1254, 1256 (Fed.Cir.2007). The testimony of experts in the relevant field will often be of assistance to a judge, but the decision must ultimately be made by the court, and there is no categorical rule requiring the input of experts. See Petersen Mfg. Co. v. Central Purchasing, Inc., 740 F.2d 1541, 1548 (Fed.Cir.1984) (<HOLDING>); Seattle Box Co., Inc. v. Indus. Crating &
holding where movant asserts several grounds in support of its summary judgment motion and the trial court does not specify the grounds on which judgment was granted the reviewing court can affirm the judgment if any of the grounds are meritorious holding that obviousness analysis may include recourse to logic judgment and common sense available to a person of ordinary skill that do not necessarily require explication in any reference or expert opinion holding that party may not appeal summary judgment in favor of opponent when grounds opposing summary judgment asserted on appeal were not raised before trial court holding that summary judgment on grounds of obviousness did not require a supporting experts opinion holding that an experts opinion must be based on facts in evidence or within his or her knowledge and that the admission of an experts opinion is reviewed for an abuse of discretion