(February 18, 2016, 2:07 PM EST) -- DENVER — A disability insurer’s failure to notify a claimant of its denial of an administrative appeal deprived the claimant of the ability to pursue a second-level administrative appeal and submit additional medical evidence in support of a disability claim, the 10th Circuit U.S. Court of Appeals said Feb. 17 in vacating and remanding a District Court’s ruling (Allen Messick v. McKesson Corp., et al., No.15-4019, 10th Cir.)....