Doe Run Resources Corp. v. American Guarantee & Liability Insurance, 531 S.W.3d 508

Doe Run, a mining/smelting company with operations in La Oroya, Peru, was sued by minors alleging bodily injury from toxic emissions (lead, arsenic, cadmium, sulfur dioxide) released from its La Oroya facility (the Reid lawsuits).
Doe Run sought reimbursement from insurers for defense costs; it added St. Paul under a Commercial General Liability policy covering bodily injury occurring outside the U.S. (Dec 2005–Nov 2007), subject to exclusions.
St. Paul denied a duty to defend, invoking the policy’s pollution exclusion (which excludes injury or damage resulting from pollution on a protected person’s premises) and an other-insurance/excess argument; Doe Run argued the exclusion was ambiguous and that St. Paul was a primary insurer.
The trial court granted summary judgment to Doe Run, finding the pollution exclusion ambiguous and awarding Doe Run defense costs and prejudgment interest; St. Paul appealed.
The appellate court reviewed de novo and considered whether the pollution exclusion unambiguously barred defense coverage for toxic-tort claims alleging environmental particulate emissions from Doe Run’s facility.

Issue	Doe Run's Argument	St. Paul’s Argument	Held
Whether the pollution exclusion bars the duty to defend	Exclusion ambiguous because it does not list "lead" or metals; an ordinary insured could view metals as products, not pollutants (relying on Hocker Oil)	Lead particulates and alleged toxic emissions are unambiguously "pollutants"/contaminants excluded by the policy	Pollution exclusion is unambiguous and bars coverage; no duty to defend
Whether allegations in the Reid petitions transform exclusion into ambiguity	The petitions reference storage/use of lead, suggesting injuries from commercial products rather than pollution	Petitions allege injury from negligent release of toxic substances into environment, not injury from sale/use of products	Allegations concern environmental releases; Hocker Oil inapplicable; exclusion controls
Whether other-insurance provision precludes coverage (primary vs excess)	St. Paul is a primary insurer and other-insurance clause cannot preclude duty to defend	St. Paul argued the other-insurance clause eliminates its duty (alternative argument)	Court did not reach this issue because exclusion precluded duty to defend
Recoverability of defense costs before tender to insurer	Doe Run sought reimbursement for defense costs incurred prior to tendering to St. Paul	St. Paul argued it owed no reimbursement for costs incurred before March 2012 tender	Court reversed trial judgment; appellate opinion did not award pre-tender costs because no duty to defend under policy

ITT Comm’l Fin. Corp. v. Mid-Am. Marine Supply Corp., 854 S.W.2d 371 (Mo. banc 1993) (summary judgment standard/de novo review)
Mendenhall v. Prop. and Cas. Ins. Co. of Hartford, 375 S.W.3d 90 (Mo. banc 2012) (insurance-contract interpretation; plain meaning rule)
Hocker Oil Co. v. Barker-Phillips-Jackson, Inc., 997 S.W.2d 510 (Mo. Ct. App. 1999) (pollution exclusion ambiguous where gasoline not listed; relied on by insured)
McCormack Baron Mgmt. Servs., Inc. v. Am. Guar. & Liab. Ins. Co., 989 S.W.2d 168 (Mo. banc 1999) (duty-to-defend assessed by comparing policy language to underlying complaint)
Doe Run Res. Corp. v. Lexington Ins. Co., 719 F.3d 868 (8th Cir. 2013) (similar pollution-exclusion holding barring toxic-tort coverage)
Rodriguez v. Gen. Accident Ins. Co. of Am., 808 S.W.2d 379 (Mo. banc 1991) (courts must not create ambiguities in unambiguous policies)
Schmitz v. Great Am. Assur. Co., 337 S.W.3d 700 (Mo. banc 2011) (use ordinary/dictionary meaning when policy terms undefined)