Facebook has created three Bay Area work hubs that each total at least one million square feet, following big leases with two legendary developers that widen its Silicon Valley footprint.
The tech titan could employ as many as 19,000 in the expansion sites, located in Fremont, Sunnyvale and Menlo Park.
The social networking giant is already expanding in its hometown of Menlo Park and has signed a mammoth lease in Sunnyvale. Now, it has signed major leases with Sobrato Organization and Peery Arrillaga totaling 18 buildings in a part of Fremont near the Dumbarton Bridge's east end.
The most recent set of leases in Fremont total 1.04 million square feet, according to Facebook.
Here's how the Fremont transactions break down: 750,000 square feet in rental deals with Peery Arrillaga and 290,000 square feet in leasing agreements with Sobrato. This news organization previously reported in November that Facebook leased 190,000 square feet from Sobrato, but now, Facebook has taken an additional 100,000 square feet.
"This new space, with its proximity to our headquarters in Menlo Park, will support our growing workforce," said Jamil Walker, a Facebook spokesman.
Facebook, in addition to ongoing construction of new offices next to its main headquarters at 1 Hacker Way, also has proposed creation of a mixed-use village of office buildings, retail, homes and parks that would include 1.75 million square feet of offices in Menlo Park.
In March, Facebook signed a lease with developer Jay Paul for 1 million square feet of Sunnyvale offices in three buildings.
Together, the expansions total 3.975 million square feet.
Of the up to 19,000 workers who could be employed across the three cities' expansion sites, the Willow Campus site in Menlo Park could possibly accommodate 7,000 to 8,700 employees.
In Fremont, the expansion "makes total sense for Facebook," said Stephen Levy, director of the Palo Alto-based Center for Continuing Study of the California Economy. "The Fremont campus is a direct play to take advantage of the folks who live in the East Bay who might be able to find a better commute."
Similarly, creating a huge campus in Sunnyvale also could help to ease some commute routes for Facebook workers.
"Facebook expanding in Sunnyvale creates better exposure to the San Jose part of the Santa Clara County workforce," Levy said.
Similarly, tech titans such as Cupertino-based Apple and Mountain View-based Google have established outposts in multiple areas beyond their hometowns, including north San Jose, Sunnyvale, Redwood City and Santa Clara.
In downtown San Jose, Google intends to develop a village of offices, shops, restaurants, housing, parks and other amenities where 15,000 to 20,000 of the search giant's employees could eventually work.
The Fremont buildings that Facebook has leased include 15 sites owned by Peery Arrillaga and three buildings owned by the Sobrato firm.
It's possible the Ardenwood district could be more closely linked to Facebook's Menlo Park hub through a rapid bus link on the Dumbarton Bridge, or by rail on an old train route over the Bay.
"Facebook probably won't wait for the rail or bus bridge to expand in Fremont," Levy said. "They could run shuttles to the BART stations nearby."
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