Covid-19 has caused trillions in business losses. Whether those losses are covered by commercial property insurance is an existential issue for both policyholders and insurers. But before that legal battle, the battlefield must be chosen. Do these coverage suits belong in federal or state court? In July 2020, a group of 42 Chicago restaurants and bars filed a lawsuit in Illinois state court against 19 commercial property insurers, seeking coverage for Covid-19 business losses,[1] in what plaintiffs’ counsel called the “mother of all” Covid-19 coverage suits.[2] A few days later, the same counsel filed a suit in New York state court on behalf of 94 restaurants and bars against 41 insurers.[3] Both suits allege that the insurers wrongly denied coverage,…