U.S. stocks opened fractionally higher Wednesday ahead of an expected Federal Reserve rate hike and following a landmark decision against U.S. antitrust regulators who tried to block the proposed merger of AT&T (T) and Time Warner (TWX) . The Dow Jones Industrial Average added 22.98 points to 25,342.71 shortly after the opening bell, while the S&P 500 tacked on 1.41 points to 2,788.26 and the Nasdaq Composite was 12.19 ticks ahead at 7,715.99. Markets are awaiting a Federal Open Market Committee decision on interest rates, with analysts widely expecting the central bank to announce a 0.25% rate hike at 2 p.m. ET. Meanwhile, AT&T was down some 4.1% at $32.93 shortly after the open after winning court approval Tuesday to take over Time Warner.