adjective. Of or relating to a word, phrase, or logo that is used or registered as a trademark.

verb. Simple past tense and past participle of trademark.

adjective. (of goods and merchandise) labeled with proprietary (and legally registered) identification guaranteeing exclusive use

"The store, which was photographed by an expatriate blogger who uses the handle BirdAbroad, has a sign identifying it as an Apple Store—a term trademarked by Apple—but is neither an Apple Store nor an Apple authorized reseller, according to store employees and an Apple list of its retail outlets."

proprietary  

trademark