Wall Street opens flat ahead of Yellen testimony

Traders work on the floor of the New York Stock Exchange May 7, 2014. REUTERS/Brendan McDermid

NEW YORK (Reuters) - U.S. stocks opened flat on Thursday after initial jobless claims data pointed to a possible strengthening in the labor market and ahead of testimony by Federal Reserve Chair Janet Yellen. The Dow Jones industrial average was up 3.31 points, or 0.02 percent, at 16,521.85. The Standard & Poor's 500 Index was down 1.75 points, or 0.09 percent, at 1,876.46. The Nasdaq Composite Index was down 15.52 points, or 0.38 percent, at 4,052.16. The Nasdaq was pressured again by weakness in Internet stocks. Priceline fell 3.2 percent to $1,095 while TripAdvisor Inc was off 2.1 percent to $82.19. (Reporting by Ryan Vlastelica; Editing by Bernadette Baum)