Update (June 4): After announcing initially a public stock offering of 4.25m shares to fund its acquisition of five properties owned by Rockwood Capital and affiliates and managed by 365 Main (see original story below), Digital Realty Trust increased the amount of shares to be sold to 6m and announced pricing of the offering. At $57 per share, the provider expects to raise up to about $327.8m. DRT plans to close the offering on June 8.

Following is the original story from June 2, 2010

Wholesale data center provider Digital Realty Trust has entered into an agreement to buy the data center portfolio of Rockwood Capital and 365 Main. The acquisition includes three properties in the San Francisco Bay Area, one in Arizona and one in Virginia. The total cost of the acquisition is about $725m, according to a DRT news release.

The deal will add 919,000 sq ft of space to the San Francisco, Calif.-based provider's already enormous roster. It includes 250,000 sq ft of land for new data center development in Arizona and uninstalled infrastructure components worth $13m. The California data centers are in San Francisco, El Segundo and Oakland. The other two are in Chandler, Ariz., and Chantilly, Va.

"Upon closing, the addition of these high-quality mission-critical data center facilities to our operating portfolio will further extend our leadership position as the largest wholesale datacenter provider in the U.S.," DRT CEO Michael Foust said in a statement. "The portfolio is leased to a diverse roster of over 200 tenants in various industries."

Rockwood Capital and its affiliates own majority of the ventures that own the said data center portfolio and 365 Main manages the facilities. The company's data center in Newark, Calif., was not part of the deal.

DRT will fund the transaction using available cash, proceeds from sale of debt or equity and its revolving credit facility. Its financial advisors in the acquisition are Credit Suisse Securities and Citi. The company expects to close the deal in early July.

On Wednesday, DRT announced a plan to sell 4.25m shares of common stock in an underwritten public offering. It intends to use the proceeds to fund the acquisition and for future expansion. DRT's stock traded at $56.64 per share on Wednesday morning, making the potential total proceeds from the sale about $240.72m.

This is the latest in a series of acquisitions DRT has done over the past year. The company has been expanding aggressively by buying land and building and by buying completed data centers, many of which have been leased out. The latest acquisition came late last month, when DRT said it had purchased two shell buildings in Santa Clara. The company had already bought another property in Santa Clara earlier that month.