Republican attorneys general accuse three of the world’s biggest asset managers of conspiring to depress U.S. coal output. It’s a first-of-its-kind and closely watched test of whether corporate alliances on climate efforts violate antitrust laws.By Deep VakilSince 2022, Republican lawmakers in Congress and state attorneys general have sent letters to major banks, pension funds, asset managers, accounting firms, companies, nonprofits and business alliances, putting them on notice for potential antitrust violations and seeking information as part of the Republican pushback against “environmental, social and governance” efforts such as corporate climate commitments.