The second-tallest skyscraper in London after the Canary Wharf Tower, the Gherkin is the latest addition to London's collection of distinctive landmarks. Like Canary Wharf, it's a multiple-occupancy office building in the City, the financial sector of London. Unlike Canary Wharf, it's not a secret headquarters for Mages (or any other supernatural faction). In fact, it's remarkably free of any kind of known supernatural influence. Three Mages and two Uratha work there in their "day jobs", but the companies they work for are totally mundane. None of the Big Three have ever tried to stake a claim to it, or base any of their operations there.
Nobody knows quite why that is. A few Mages, naturally, suspected some sort of Fate magic at work, and examined the building minutely for signs, with no results whatsoever. (Well, apart from that embarrasing little matter of the two Free Council Mages and the dodgy long derivatives positions, but the Fate magic employed there had nothing to do with keeping anyone out of the building). It seems to be nothing more than a perfectly genuine co-incidence.