Rossello v. Zurich Amer. Insurance, 226 A.3d 444

In 1974 Rossello was exposed to asbestos during work; he developed mesothelioma and was diagnosed in 2013.
Mitchell (the installer) was insured by Maryland Casualty (now Zurich) under CGL policies from Jan. 1, 1974 to July 31, 1977; policy language defined “bodily injury” as occurring during the policy period and “occurrence” to include continuous exposure.
Rossello obtained a reduced final judgment of $2,682,847.26 against Mitchell; he sought to collect from Zurich via garnishment.
Zurich argued that liability should be prorated by time-on-the-risk across all insured/insurable years (Zurich advocated either 1974–2013 or, more reasonably, 1974–1985 as the last year asbestos coverage was commercially available); Rossello argued Zurich must pay the entire judgment under an “all sums”/joint-and-several theory.
The circuit court applied pro rata, time-on-the-risk allocation across the insured/insurable period (1974–1985), awarded partial judgment of $613,233 pending further calculation, and the Court of Appeals affirmed.

Issue	Rossello's Argument	Zurich's Argument	Held
Proper allocation method for long‑latency continuous bodily injury (pro rata v. joint‑and‑several)	CGL promises to pay “all sums” — each triggered policy must cover the full judgment (joint‑and‑several / all‑sums).	Adopt pro rata time‑on‑the‑risk: each insurer pays only its share for years it was on the risk.	Pro rata allocation by time on the risk is correct; joint‑and‑several is incompatible with CGL language and continuous/injury‑in‑fact trigger.
Relevant temporal span for proration (which years to include)	Allocation should run from exposure (1974) through manifestation/diagnosis (2013).	Limit allocation to insured and insurable years; commercial availability ends in 1985, so allocation is 1974–1985 (insured years plus years insurance was reasonably available).	Use insured + insurable years; here 1974–1985. Gaps for which insured elected no coverage are borne by the insured unless coverage was unavailable.
Who bears burden to prove coverage unavailability in gap years	(Rossello) Not directly argued as primary; seeks full recovery from insurers.	Zurich: insured bears risk unless defendant proves coverage unavailable; Zurich said coverage ceased being available after 1985.	The party asserting unavailability bears the burden; Mitchell offered no evidence that coverage was unavailable for 1977–1985, so allocation included those years.

Lloyd E. Mitchell, Inc. v. Maryland Casualty Co., 324 Md. 44 (1991) (rejected manifestation‑only trigger for asbestos; exposure can trigger coverage)
Bausch & Lomb, Inc. v. Utica Mutual Ins. Co., 355 Md. 566 (1999) (declined to adopt joint‑and‑several allocation; remanded for year‑by‑year damage proof)
Mayor & City Council of Baltimore v. Utica Mut. Ins. Co., 145 Md. App. 256 (2002) (adopted pro rata time‑on‑the‑risk allocation for continuous injury)
United Servs. Auto. Ass’n v. Riley, 393 Md. 55 (2006) (confirmed continuous/injury‑in‑fact trigger can implicate multiple policy periods)
Keene Corp. v. Ins. Co. of N. Am., 667 F.2d 1034 (D.C. Cir. 1981) (advocated the minority “all sums”/joint‑and‑several approach)
Owens‑Illinois, Inc. v. United Ins. Co., 650 A.2d 974 (N.J. 1994) (discussed competing trigger theories and injury‑in‑fact concept)