N840VB is taken. It's currently assigned to a Shield Ai Inc V-BAT registered in Frisco, TX.
See the full aircraft record →A tail number only frees up if the owner deregisters the aircraft or moves it to a different N-number — and even then the FAA holds it before releasing it to the public.
N840VB has been worn before. Past registrations from FAA deregistration records:
Tails one nudge away from N840VB that aren't assigned or reserved: