It took only seven years, but GlaxoSmithKline P.L.C. finally said that Philadelphia is not its U.S. headquarters.

Up till now, the company said it considered Philadelphia and Research Triangle Park dual U.S. headquarters. The arrangement was a holdover from the 2001 merger between SmithKline Beecham and Glaxo Wellcome, two British drug makers with major operations in both of those areas.

The notion of maintaining dual headquarters always struck me as utter fiction. Done for political purposes, I’m sure. But a true dual headquarters sounds like an awfully wasteful way to spend your capital.

Sure, former CEO Jean-Pierre Garnier had an office in GlaxoSmithKline’s offices at 1601 Race St. and a house in Devon. His successor, Andrew Witty, who has been frantically restructuring the drug giant, told Inquirer staff writer Miriam Hill in July that he was looking for a home in Philadelphia. Yesterday, a company spokesperson said he owns property here but was not sure whether he owns any in North Carolina.

In the name of reducing confusion, GlaxoSmithKline now says its operations in the Raleigh-Durham area of North Carolina are its only U.S. headquarters. Call it another blow to the cool factor of Center City Philadelphia being the must-have address for corporate headquarters.

So, dear readers, you’ll never have to read the awkward phrase “GlaxoSmithKline, which has a U.S. headquarters in Philadelphia” in The Inquirer ever again.

And, for the record, GlaxoSmithKline is not based in London proper. It’s in Brentford, a suburb of London. So there, London. UPDATED AS OF NOV. 6: ***My sarcasm got in the way of the facts. Brentford is in London, as a London-born executive who works for a Philadelphia-area company tells me. It's closer to Heathrow airport than the Tower of London, but it's still London. Specifically, Brentford is in the London borough of Hounslow. Philadelphia may be a city of neighborhoods, but London is a city of boroughs.***

Saying you have two headquarters is only slightly more believable than labeling someplace a headquarters where the CEO rarely makes an appearance. Bell Atlantic Corp. called Philadelphia its corporate headquarters for years, but it was plain that Arlington, Va., was where the real power was. After Bell Atlantic bought Nynex in 1997, forming what would become Verizon, it proclaimed New York its headquarters and that was that.

Word of Philadelphia’s demotion in corporate stature came the same day the drug company told its workforce that it would be cutting 1,800 U.S. jobs just in time for the holidays. It’s not clear how many of those cuts will fall on the 5,000 people GlaxoSmithKline employs in Center City and Philadelphia’s western suburbs.

The stain on Philadelphia’s image from losing a headquarters is pretty minor compared with the loss of real jobs.

But it can’t help those who market Philadelphia as a place to do business. A big corporation decides that a campus-like office park is more preferable for its headquarters than an office building in a rejuvenated downtown area? Ouch.

The gain or loss of a corporate headquarters can be spun any which way. We tend to minimize the impact when we lose one and go overboard with the hype when some large company deems Philadelphia worthy enough to change all of its stationery.

GlaxoSmithKline will to continue to employ thousands in the Philadelphia region and should play a big role in corporate philanthropy here.

But coming as it does after delays in relocations by Unisys Corp. and BlackRock Inc., I bet Mayor Nutter’s administration sees little upside to yesterday’s announcement.