Twitter's Data Business Proves Lucrative

Twitter earned $47.5 million from selling off its data to a fast-growing group of companies that analyze the data for insights into news events and trends. That is a small amount compared with the revenue generated from advertising, but Twitter's data business has rippled across the economy.

The site's constant stream of experiences, opinions and sentiments has spawned a vast commercial ecosystem, serving up putative insights to product developers, Hollywood studios, major retailers and -- potentially most profitably -- hedge funds and other investors. Backed by millions of dollars in venture capital, hundreds of "social listening" firms have emerged.