this taken?

(Is) this taken?

Is someone already occupying or using this (section of space)? Used especially in reference to a seat in a building or on a vehicle. A noun or pronoun can be used between "this" and "taken" to specify the section of space the speaker is referring to. Excuse me, sorry to disturb you, but is this seat taken? "This compartment taken?" she said to the man going into the adjacent room on the train. A: "Hey, what are you doing?" B: "Oh, I'm sorry, is this taken?" A: "Yeah, I was studying at that desk! I just got up to use the bathroom."
See also: this

(Is) this (seat) taken?

an inquiry made by a person in a theater, auditorium, etc., asking someone already seated whether an adjacent seat is available or already taken. Finally, Bill came to a row where there was an empty seat. Bill leaned over to the person sitting beside the empty seat and whispered, "Is this seat taken?" Fred: 'Scuse me. This taken? Alice: No. Help yourself.
See also: this