Trading volume in Gilead Sciences jumped 260 percent on Friday over its 10-day average, after the biopharmaceutical company reported positive results from an early clinical trial of a recently acquired hepatitis C drug.
Here's a look at other stocks in the S&P 1,500 index that displayed unusual volume in the trading session.
S&P MidCap 400: Dresser Rand volume increased 480 percent over its 10-day average, as the manufacturer of gas turbines lowered its fourth-quarter revenue outlook.
S&P SmallCap 600: STR Holdings volume rose 600 percent over its 10-day average, after the maker of components for the solar industry forecast a fourth-quarter loss.
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