AAI has been at the forefront of maintaining antitrust’s historic concern with monopolies, exclusionary conduct, and harmful vertical restraints. Courts and antitrust enforcers have significantly narrowed the scope of monopoly enforcement under Section 2 of the Sherman Act. Since 1998, our progressive approach has been a long-standing counterweight that has become all the more important in light of increasing market concentration in numerous sectors where lax merger enforcement and permissive conduct rules have created and sustained dominant firms. AAI advocates for aggressive enforcement to combat exclusionary conduct by dominant firms and a renewal of antitrust’s skepticism of durable monopolies. We support efforts to strengthen anti-monopoly law and have been instrumental in efforts to craft comprehensive legislative proposals to put monopoly enforcement back into the agencies and the courts. Below is a sampling of some of AAI’s leading contributions and victories on the monopolization front.