MarketWatch: Warren Buffett’s Berkshire Hathaway reduced its stake in several media-company holdings — including Charter Communications, Viacom and Liberty Global — in the first quarter. Berkshire sold 219,101 shares of Charter, which has been pushing a merger with fellow cable operator Time Warner Cable. Berkshire also sold 473,531 shares of Liberty Global. It also sold 361,111 shares of Viacom. Additionally, Berkshire increased its stake in 21st Century Fox.