>www.loopnet.com/Listing/1750-Old-Meadow-Rd-McLean-VA/4070902/
not necesserily.
It is not uncommon for a broker/agent to update vacancies for a unit over time.
While it may seem that all units/floors have been vacant since 2016, it is possible (probable) that the original listing was for a single unit.
I have done this myself with listings.