United Parcel Service won an early battle in its fight against a group of cannabis companies it accuses of trademark infringement.

UPS accuses United Pot Smokers, UPS420, and THCPlant of infringing on its family of trademarks, including its famous shield logo. While the case is ongoing, the U.S. District Court for the Central District of California temporarily blocked the defendants from using the allegedly infringing marks.

These companies market and sell cannabis products, and offer delivery and logistics services for...