NEW YORK ( TheStreet) -- Netflix ( NFLX) shares surged as much as 20% after legendary activist investor Carl Icahn took a large stake in the movie-streaming and DVD-rental company. Icahn on Wednesday disclosed in a filing with the Securities and Exchange Commission he has a 9.9% stake in Netflix, or 4,291,066 shares. Netflix shares rose sharply in reaction to Icahn's disclosure, jumping 20% before briefly being halted in Nasdaq trading. Upon resumption of trading late on Wednesday, Netflix shares were up 14% to $79.56. The company's stock has gained over 20% this year, as the news of Icahn's stake is helping to stem a slide from March's highs of $120-plus. The filing didn't say if Icahn plans to nominate board seats to the struggling video service. For Icahn, his newly unveiled Netflix stake represents a return to the tech sector after waging a successful campaign for the breakup of Motorola into Motorola Mobility and Motorola Solutions ( MSI). In August 2011, Motorola Mobility was sold to Google ( GOOG), in one of the largest technology deals since the financial crisis. In recent days, Netflix has been rumored to be under the gaze of Microsoft ( MSFT). Company officials denied the speculation. At this time last year, Netflix CEO Reed Hastings mapped out a plan to split the company's streaming subscription business from its mail-order unit. Investors and analysts balked, prompting the company to retreat from its plan. Earlier in October, Icahn submitted a tender offer for military truck maker Oshkosh ( OSK) in a $3 billion bid worth $32.50 a share. The Wisconsin-based company's board quickly rejected Icahn's offer, signaling he may need to make a buyout pitch directly to shareholders. Netflix stands out as Icahn's most notable investment of the fall after he successfully imparted a host of board changes at struggling oil and gas giant Chesapeake Energy ( CHK), and was seen as instrumental in the company's divestiture of billions in non-core exploration and midstream assets. In August, after a rare win in a tender offer campaign for refiner CVR Energy ( CVI), Icahn withdrew his bid and is now in the process of IPO-ing individual pieces of the company. For more on Carl Icahn, see his investment portfolio. Follow @agara2004-- Written by Antoine Gara in New York.