Cuban Beefs Up Rentrak Stake

Billionaire tech guru and Dallas Mavericks owner Mark Cuban has been beefing up his stake in ratings measurement company Rentrak. According to SEC filings Thursday, Cuban owns 972,900 shares of Rentrak, or about 8.7% of its outstanding stock. A long time investor in Rentrak -- he began buying the stock back in 2004 -- Cuban added about 207,000 shares of the company in August for about $2.4 million. According to the filing, Cuban paid $9.3 million for the entire stake, all out of his personal fortune.

Cuban has been a long-time booster of the company - he became involved through his interest in Landmark Theaters, which is a customer of Rentrak's measurement products. In 2009 his HDNet also became a Rentrak customer.