Requirement for pro rata allocation of defense costs among successive insurers

The California Third District Court of Appeals recently required pro rata allocation of defense costs among successive insurers. In Certain Underwriters at Lloyds, London v. Arch Specialty Ins. Co., 246 Cal.App.4th 418, 200 Cal.Rptr.3d 786 2016 WL 1436362 (3rd Dist. 2016), the Court reaffirmed California public policy as prohibiting enforcement of “escape” other insurance clauses inequitable contribution actions between successive primary insurers seeking to allocate the cost of defending construction defect litigation. Under existing law, each insurer was responsible for a pro rata share of defense costs notwithstanding the fact that one insurer’s policy contained language in both the insuring agreement and the conditions section both stating that the insurer had a duty to defend only if no other insurance afforded a defense. The Court found that the placement of the escape language in the insuring agreement was not sufficient to differentiate the case from prior California precedent prohibiting the enforcement of escape other insurance clauses which appeared elsewhere in the insurance policy.