From CSIS:

The State Antitrust Enforcement Venue Act has amassed broad bipartisan support in Congress; over 100 Republicans have signed a discharge petition to call for a House floor vote, and prominent Democrats have backed it as well. Yet some critics, including those at the U.S. Chamber of Commerce and R Street Institute, argue that decentralizing such lawsuits would reduce efficiency in competition enforcement. In other words, defendants might have to answer to simultaneous proceedings across multiple districts or jurisdictions, which could subsequently drive up costs for both private companies and court systems. These critics have voiced further concern that if, hypothetically, multiple state lawsuits address similar conduct, uncertainty might arise from contrasting judicial decisions across various courts and jurisdictions.