Sun has been looking for an East Bay location to attract new employees and reduce commute times for some of its existing Bay Area employees. The Alameda County Board of Supervisors approved the $43.12 million purchase and sale agreement Tuesday. It was the county's last available parcel for office space. Three parcels adjacent to the BART station are available for 1,500 apartments and a hotel.

The county acquired the so-called Santa Rita property in 1965 for $1.5 million and bolstered its holdings in the 1990s with a $4 million purchase from the Army. In 1995, the county renamed its former Santa Rita property Emerald Park to market it to firms with an interest in Dublin.

Since then, it has sold parcels to Oracle and Cisco Systems, among others. In November, the county closed a $45 million land deal with Cisco. The company plans to break ground later this year on the first phase of a 1-million-sf office development. The county expects to net about $300 million from the Santa Rita property.