Danhua Capital has invested in some of Silicon Valley's most promising startups in areas like drones, artificial intelligence and cybersecurity. The venture capital firm is based just outside Stanford University, the epicenter of U.S. technology entrepreneurship.

Yet it was also established and funded with help from the Chinese government. And it is not alone.

More than 20 Silicon Valley venture capital firms have close ties to a Chinese government fund or state-owned entity, according to interviews with venture capital sources and publicly available information.