A coalition led by New Hampshire is asking the U.S. Supreme Court to limit how Massachusetts applies its firearms permitting regime to out-of-state visitors. In a brief supporting petitioner Philip Marquis of Rochester, New Hampshire, attorneys general from 24 other states argue that Massachusetts license-to-carry requirement should not apply to nonresidents who are legally armed at home but cross into the Bay State without a Massachusetts permit. The filing spotlights a practical flashpoint at the Pheasant Lane Mall in Nashua, where part of the parking lot extends over the state line into Tyngsborough, Massachusetts. A visitor could be lawful on the New Hampshire side and, by stepping across the line, face felony exposure next door. The multistate brief contends that nonresident visitors engaged in otherwise lawful carry should not be forced to obtain a Massachusetts license merely because a property straddles an invisible boundary. New Hampshires filing warns that a person who is legally carrying in most of the mall could become a felon simply by crossing into the Massachusetts portion without a Bay State license. Massachusetts officials counter that the states licensing rules apply evenhandedly to residents and nonresidents and that the regime is aimed at keeping firearms out of prohibited hands consistent with the Commonwealths public-safety objectives. Marquiss individual case provides the vehicle for Supreme Court review. According to the petition, he was involved in a 2022 traffic accident on Interstate 495, told responding officers he had an unloaded pistol in his pocket, and acknowledged he did not possess a Massachusetts license. He maintains he was eligible to carry in New Hampshire because he was not federally disqualified. Massachusetts law requires both residents and nonresidents to obtain a license before carrying; nonresidents can apply through the State Police for a temporary license, which carries a fee and requires approval. A lower court convicted Marquis of unlawful possession of a firearm and ammunition, and in March the Massachusetts Supreme Judicial Court upheld the conviction and the laws constitutionality. The petition frames the dispute within the Supreme Courts 2022 decision in New York State Rifle & Pistol Association v. Bruen, which invalidated discretionary may issue carry permitting and instructed lower courts to assess modern gun regulations against the nations historical tradition. New Hampshire and the allied states argue that Massachusetts approach, when imposed on nonresidents in transit, functions like a modern barrier to ordinary carry and lacks adequate historical support. They also raise Fourteenth Amendment concerns, asserting that travelers should not face felony penalties merely for moving between adjacent jurisdictions that share a single commercial space. For gun owners, instructors, and retailers in the New HampshireMassachusetts border area, the practical issues are immediate. Properties that cross the state line, like the Pheasant Lane Mall complex, present exposure for nonresidents who assume their home-state rules follow them across a parking lot. Until the Supreme Court acts, Massachusetts licensing requirement remains enforceable, and nonresidents should assume they need Massachusetts authorization to carry on the Massachusetts side of any bisected venue. Trainers serving cross-border clients may want to emphasize route planning, recognition of jurisdictional boundaries on shared properties, and clear guidance on where and how to secure a firearm before entering Massachusetts without a license.