In 1999, ISO, following the lead of a number of companies, introduced a series of new and revised "Montrose" endorsements for the CGL program. This filing was prompted by a California Supreme Court decision, Montrose Chemical Corp. v. Admiral Ins. Co., that adopted the "continuous trigger" of coverage under third-party liability claims and abdicated the "loss-in-progress" or "known loss" rule that was at the foundation of insurance. The information below examines the background, coverage changes and implications of the Montrose decision.

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