Federal law prohibits marijuana and its transportation across state lines; but the new number of cannabis-friendly states sharing borders may end up testing that ban.

Federal law prohibits marijuana and its transportation across state lines; but the new number of cannabis-friendly states sharing borders may end up testing that ban.

DENVER — Normally, when a company based in one state wants to sell products in another state, it starts calling truckers. For Strainz, a Las Vegas marijuana company, it was more complicated.