Obviousness analysis under 35 U.S.C. § 103

QUESTION PRESENTED In conducting an obviousness analysis under 35 U.S.C. § 103, did the Federal Circuit err in holding that there “is no basis in our case law” for requiring an articulated basis for choosing a reference in a prior art combination as the primary reference, when such a basis is required to comply with controlling precedent in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 421, 127 S. Ct. 1727, 1742, 167 L. Ed. 2d 705 (2007), WBIP, LLC v. Kohler Co., 829 F.3d 1317, 1337 (Fed. Cir. 2016), and Yeda Rsch. v. Mylan Pharms. Inc., 906 F.3d 1031, 1044-45 (Fed. Cir. 2018), and where the choice of primary reference was dispositive?