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The presence of the University of California, San Diego and other research institutions has helped to fuel biotechnology growth. In 2013, San Diego has the second-largest biotech cluster in the United States, below the Boston area and above the San Francisco Bay Area. There are more than 400 biotechnology companies in the area. In particular, the La Jolla and nearby Sorrento Valley areas are home to offices and research facilities for numerous biotechnology companies. Major biotechnology companies like Illumina and Neurocrine Biosciences are headquartered in San Diego, while many biotech and pharmaceutical companies have offices or research facilities in San Diego. San Diego is also home to more than 140 contract research organizations (CROs) that provide a variety of contract services for pharmaceutical and biotechnology companies.

How many contract research organizations are in San Francisco?
unanswerable