Indiana has traditionally been thought of as an “all sums” jurisdiction. Allstate Ins. Co. v. Dana Corp., 759 N.E.2d 1049, 1060 (Ind. 2001) (“whether or not the damaging effects of an occurrence continue beyond the end of the policy period, if coverage is triggered by an occurrence, it is triggered for ‘all sums’ related to that occurrence.”) However, the Indiana Supreme Court – over the strident dissent of its Chief Justice and one other Justice of the five Justice court – recently refused to hear an appeal from an intermediate appellate court decision which applied pro rata allocation in an insurance coverage action involving long-tail toxic exposure claims asserted by former employees against the insured. Thomson Inc. v. Ins. Co. of N. Am., 2015 Ind. LEXIS 397 (Ind. May 15, 2015).

In Thomson, the insured was sued by former Taiwanese employees who were allegedly exposed to industrial solvents from 1970 through 1992. These employees claimed that this exposure caused cancer, or increased their risk of developing cancer in the future.  The insured sought defense and indemnity under commercial general liability policies issued to it between 1991 and 2007. The insured contended that an all sums allocation method applied under the Indiana Supreme Court’s holding in Dana. The trial court agreed and issued an “all sums” ruling.

The appellate court reversed the trial court’s allocation holding. The appellate court distinguished Dana based on differences in the applicable policy language. Specifically, the insuring agreements at issue in Dana required the insured to “indemnify the insured for all sums. . .” the insured became obligated to pay because of an occurrence. Id. at n. 3-4. In contrast, the insuring agreements in the Thomson policies required the insured to “pay those sums. . .” the insured became obligated to pay “during the policy period.” Id. at 1003. The Thomson court held that this different, “limiting” policy language merited a departure from Dana: “the plain meaning of the limiting phrases ‘those sums’ and ‘during the policy period’ and does not render any of the remaining language meaningless.” Id. at 1020. In other words, the Thomson insurers only were required to cover damages occurring during the policy period and not all damages resulting from any occurrence during the policy period.

However, the Thomson court did not provide any guidance to the trial court as to the proper pro rata allocation method: it did not indicate whether “time on the risk,” “years and limits,” or some other method was advisable. Rather, the court remanded the allocation issue to the trial court:

The trial court will be best situated to select (and customize, if necessary) the fairest method of apportioning liability among the insurers in light of the factual complexities of the case at the appropriate time. And for that reason, we believe that the trial court should be afforded broad discretion in selecting and applying an apportionment method.

Id. at 1022-23.

There is no “one-size-fits-all” approach to allocation in Indiana in light of Thomson. Rather, as the Supreme Court dissenters recognized, courts applying Indiana law must engage in careful scrutiny of policy language to determine proper allocation in long-tail exposure cases. See Thomson Inc. v. Ins. Co. of N. Am., 2015 Ind. LEXIS 397, *2 (Ind. May 15, 2015) (Rush, C.J., dissenting) (“We should not burden trial courts with that task [of determining allocation] based on policy language that is ambiguous at best.”)