Mealey's (April 7, 2020, 11:22 AM EDT) -- SAN FRANCISCO — The California Supreme Court on April 6 reversed an appellate court’s ruling that excess policies implicated in an environmental contamination coverage dispute are subject to horizontal exhaustion after determining based on the language in the policies that a rule of vertical exhaustion is appropriate (Montrose Chemical Corporation of California v. Superior Court of the State of California, et al., No. S244737, Calif. Sup., 2020 Cal. LEXIS 2095)....