TikTok Inc on Monday filed a lawsuit challenging the state of Montana’s new ban on use of the Chinese-owned app, the first state to bar the popular short-video sharing service. TikTok argues the ban, which would take effect on Jan. 1, violates First Amendment rights of the company and users. The lawsuit, filed in U.S. District Court in Montana, also argues the ban is pre-empted by federal law because it intrudes upon matters of exclusive federal concern and violates the Commerce Clause of the U.S. Constitution, which limits the authority of States to enact legislation that unduly burdens interstate and...