SecondMarket

For maintaining the largest market for private-company shares. Facebook is the most obvious beneficiary of a private company leveraging the liquidity that SecondMarket can offer a company before it goes public. The market has benefited greatly from Facebook’s involvement–30% of its revenue came from trading in its shares–but the market is working with a couple hundred private companies to manage private stock sales. SecondMarket, which managed $558 million in transactions last year, is hoping to expand beyond startups: Trendy food companies such as In-N-Out Burger and Dogfish Head Brewery are among the non-tech private ventures that SecondMarket investors are most interested in trading.