TULSA, Okla. (AP) — A Canadian animation studio and media company is suing an Oklahoma medical cannabis dispensary chain accusing it of infringing copyright by using a logo long-established in programming aimed at children.

Nelvana Enterprises Inc. filed a lawsuit in federal court in Tulsa last week that alleges Treehouse Dispensaries "willfully copied and is using a confusing similar imitation" of a logo it has used in children's television programming since the 1990s, the Tulsa World reported.

Nelvana, based in Toronto, said Treehouse Dispensary promised to stop using the logo but didn't pro...