150 California Street150 California Street is a 24-story, office tower skyscraper located on California Street in the financial district of San Francisco, California.HistoryConstruction of the building was completed in 2000 and the building was designed by architecture firm Hellmuth, Obata + Kassabaum. In 2002, the AIA San Francisco and San Francisco Business Times honored its designers with the 2002 Honor Award for Architecture.TenantsGCA Savvian