It's been a rough week for tech stocks, and some of Silicon Valley's top figures have paid the price. Mark Zuckerberg has lost $3.1 billion, Bloomberg reports, as Facebook dropped 11%. Google co-founders Larry Page and Sergey Brin, meanwhile, saw their joint fortunes dip $3 billion, while Amazon boss Jeff Bezos was down $1.9 billion. The market is seeing a "healthy cautiousness" tied to concerns about Russia and the Ukraine, Federal Reserve moves, and quarterly earnings reports, portfolio manager John Carey tells Bloomberg.
Facebook's plunge followed the announcement that the social network had scooped up a virtual-reality company. Google's drop came amid plans to issue 330 million nonvoting shares next week; both Google and Amazon said this week they would cut prices for services in the cloud. "With regard to frothy, speculative stocks, some people are saying maybe it’s time to take a few chips off the table," Carey says. (Read more Mark Zuckerberg stories.)