Stocks slightly pared gains after an auction of 30-year Treasuries attracted weak demand on Thursday.

U.S. Treasury debt prices extended losses, sending long-bond yields to a four-month high after the weak bond auction.

The Dow Jones industrial average <.DJI> was up 52.68 points, or 0.51 percent, at 10,389.73. The Standard & Poor's 500 Index <.SPX> was up 5.57 points, or 0.51 percent, at 1,101.52. The Nasdaq Composite Index <.IXIC> was up 9.38 points, or 0.43 percent, at 2,193.11.

(Reporting by Angela Moon, Editing by Kenneth Barry)