4. Cuban's Patent Play Put down those victory cigars all you Vringo ( VRNG) shareholders. Apparently, Mark Cuban's investment is less about your company's prowess than its patents. News that the owner of the reigning NBA champion Dallas Mavericks purchased a sizable chunk of the mobile networking software provider sent its shares up over 30% on Monday to $3.97. In a filing with the Securities and Exchange Commission on Friday, the bellicose billionaire disclosed ownership of 1.03 million common shares, representing a 7.4% stake in Vringo. Considering that Vringo is still trading below its June 2010 IPO price of $4.60, as well as the fact that it lost $7.5 million in 2011 with revenue totaling $718,000, you can understand why Cuban's maneuver left a lot of puzzled market-watchers wondering: What in the name of Dirk Nowitzki is that nut-job up to now? Was he interested in the company's Facetone app in the wake of last week's Facebook's mind-splattering $1 billion acquisition of photo-sharer Instagram? Was that the slam dunk that Cuban saw in Vringo's future? Nah, nothing of the sort. That would be playing offense, and while he can often be quite offensive to referees, Cuban knows full well that defense that wins championships. And that's exactly what his Vringo bid was all about: Good old-fashioned defense. "This is a hedge against the unlimited patent exposure all the companies I have investments in face. Patent risk is impossible to quantify," wrote Cuban in an e-mail to our good friends over at Forbes. "It's unrealistic for most small to medium businesses to have any clue which patents they are at risk over." You see folks, what really moved Mark's hand was Vringo's plans to merge with Innovate/Protect, an intellectual property-based company that owns the patent assets of long-since-forgotten search engine Lycos. Innovate/Protect is involved in patent litigation with a number of companies, including Google ( GOOG) and AOL ( AOL), alleging that they are "unlawfully using systems that incorporate features claimed in two patents owned by I/P Engine," a unit of the company. Yep, despite his long-held -- and much-blogged -- hatred for so-called patent trolls, Cuban decided that unlike the Miami Heat in last year's NBA finals, he simply could not beat them. So despite all his bluster, he joined them.