John Malone’s Liberty Media (NSDQ: LINTA) has acquired an additional 14 million shares of IAC (NSDQ: IACI), raising its stake in the company run by Barry Diller to roughly 30 percent of the economic value of IAC shares. Liberty Media paid a single holder nearly $340 million, or $24.25 per share. At the same time, the company entered into a standstill agreement—ie no stock buying (subject to customary exceptions)—with IAC that will expire April 15, 2009, or when the proposed five-way split of IAC is either accomplished or abandoned. Liberty said it “took advantage of recent weakness in IAC’s shares to increase its holding at an attractive price.” Release.

-- IAC also purchased 6 million shares of its common stock from the same shareholder at the same price for a total of $145.5 million.