(September 4, 2015, 9:44 AM EDT) -- SACRAMENTO, Calif. — A commercial umbrella liability insurance policy does not clearly specify that a self-insured retention (SIR) applies to the umbrella provision only and that the $1.5 million SIR applies to the excess provision, a California federal judge ruled Sept. 1, denying partial summary judgment to the insurer (D.R. Horton, Inc. – Sacramento v. National Union Fire Insurance Company of Pittsburgh, PA, and AIG Specialty Insurance Co., No. 14-2155, E.D. Calif.; 2015 U.S. Dist. LEXIS 117318)....