Ecolab Inc. v. Ace Property and Casualty Insurance Company, 0:23-cv-01259

Ecolab, headquartered in Minnesota, was sued in numerous lawsuits—mostly in California—for injuries allegedly caused by exposure to its OxyCide disinfectant product.
Ecolab was insured under a series of liability policies issued by ACE (now called Chubb), via policies brokered and issued to Ecolab’s Minnesota headquarters.
The key issued policies did not include a choice-of-law clause and provided nationwide coverage with specific endorsements for entities in various states.
Ecolab and ACE disputed whether Minnesota law or California law should govern insurance coverage for these lawsuits, primarily affecting how much Ecolab would need to pay before ACE’s coverage was triggered.
The immediate dispute focused on a particular California case (the “Slamer” case), involving a nurse who was injured after alleged discrete, initial exposure to OxyCide, with worsening symptoms over two policy periods.
The parties agreed to an early partial summary judgment to resolve (1) the choice of law and (2) whether Ecolab must pay one or two "retained limits" for Slamer's injuries, depending on whether her injuries were from a "single event" or constituted continuing injury across policy periods.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Which state’s law governs the coverage dispute?	California law should govern; CA contacts significant, and the policies insured nationwide risks with CA losses foreseeable.	Minnesota law should govern; policies issued to MN company, negotiated in MN.	Minnesota law applies, based on greater MN governmental interest.
How many retained limits must Ecolab satisfy for the Slamer lawsuit?	Only one retained limit (single, discrete event triggered initial harm).	Injuries were cumulative across periods, so multiple retained limits apply.	One retained limit applies (injury arose from discrete, identifiable event).

Jepson v. Gen. Cas. Co. of Wis., 513 N.W.2d 467 (Minn. 1994) (primary Minnesota Supreme Court articulation of the state’s choice-of-law methodology)
Northern States Power Co. v. Fidelity and Cas. Co. of New York, 523 N.W.2d 657 (Minn. 1994) (framework for allocation of coverage among insurers in long-tail liability claims)
Domtar, Inc. v. Niagara Fire Ins. Co., 563 N.W.2d 724 (Minn. 1997) (actual-injury theory and role of discrete, identifiable events in insurance trigger disputes)
In re Silicone Implant Ins. Coverage Litig., 667 N.W.2d 405 (Minn. 2003) (affirming that allocation is only used in ambiguous cases; discrete, identifiable events trigger all subsequent coverage)