Quintain Estates won a High Court battle this week to evict squatters from its former Mayfair offices.
A group of around 40 people had been occupying offices at 16 Grosvenor Street, the BBC reported, but were ordered to leave immediately on Wednesday.
Quintain was granted a possession order by Mr Justice Henderson, who ruled there was no case against eviction.
On Tuesday, the judge had adjourned the case to allow the squatters time to seek legal advice as to whether they had a right to remain on human rights grounds.
Quintain moved to SEB Asset Management’s 43-45 Portman Square last autumn, taking a 10-year lease.
A statement from Quintain said that since the squatters had occupied the building, the fire brigade and police had mounted operations to extinguish a fire and remove a firearm, respectively.
“In using the legal process, we have two objectives: the first is to minimise the disruption that’s been caused to people working in the neighbourhood and the second is to avoid further damage being done to the building,” the company said.