S&P 500 ends up slightly for third day

NEW YORK (Reuters) - The S&P 500 ended a third straight session of minimal gains on Thursday, helped by a flurry of merger activity, though investors expect a pullback with major averages near multi-year highs.

Based on the latest available data, the Dow Jones industrial average .DJI was down 8.98 points, or 0.06 percent, at 13,973.93. The Standard & Poor's 500 Index was up 1.07 points, or 0.07 percent, at 1,521.40. The Nasdaq Composite Index was up 1.78 points, or 0.06 percent, at 3,198.66.

(Reporting By Caroline Valetkevitch; Editing by Kenneth Barry)