The Supreme Court’s late-June grant of certiorari in challenges to AR-15-style rifle bans in Cook County, Illinois, and Connecticut has become the dominant factor behind traders pricing a narrow 55.5% chance of invalidation. A 6-3 conservative majority that has repeatedly broadened Second Amendment protections since the 2022 Bruen decision now confronts the question of whether these semiautomatic firearms qualify as “arms in common use.” Oral arguments are slated for the fall term, with a ruling expected by mid-2027. Signals from Justices Kavanaugh, Thomas, Alito, and Gorsuch suggest strong skepticism toward the bans, yet Chief Justice Roberts and Justice Barrett remain potential swing votes whose views on “common use” versus public-safety exceptions introduce meaningful uncertainty. Recent lower-court upholdings and the absence of further docket movement since June have kept probabilities tightly balanced.