KBS Realty Advisors paid $60 million or $190 per sf for the building in March on behalf of a separate account investor. A source at KBS declined to provide the name of the investor, but said it was the first acquisition in the fourth fund the company has established with this investor.

Virgin Mobil USA is a joint venture between Sir Richard Branson's Virgin Group and Sprint PCS which operates the largest all-digital, all-PCS nationwide wireless network. The company is establishing its Western regional headquarters in the building. KBS says Virgin was attracted to Mt. Diablo Plaza for its alternative location to San Francisco, as well as its proximity to executive housing, major thoroughfares, freeways and the Bay Area Rapid Transit System.

"This lease represents one of the few new tenant migrations from San Francisco to the East Bay area in over one year," says KBS Senior Vice President David Kray. Kray adds that the lease represents 20,000 sf of positive absorption in a submarket that has experienced 224,766 sf of negative absorption since the start of the year.