Investment firms in recent years have turned to so-called alternative data firms, which turn obscure data sets into tradable information, to try and get an edge on the competition. A cottage industry of tech firms has sprung up, processing information on everything from the weather to web searches and selling it to hedge funds and others. Take Thasos Group. A player in the booming $7 billion alternative-data industry, Thasos was worth $42 million, had ties to MIT, and boasted a blue-chip CEO whose prior company Sense Networks was once named the "The Next Google" by Newsweek.