Mallinckrodt - The Irish pharmaceuticals company fell after saying the Food and Drug Administration would no longer recognize its generic attention-deficit drug as equivalent to the original.
Amazon.com - The online retailer rose after reaching a deal for eBook and print book sales with Hachette Book Group.
United Continental Holdings - The carrier and others including Delta Air Lines, Alaska Air Group and Southwest Airlines gained as domestic oil prices fell.
Exxon Mobil - The oil producer and competitors including Chevron, ConocoPhillips and Hess dropped with the price of crude.
Macy's - The department-store operator fell after Wells Fargo downgraded its shares to market perform from outperform.
SunPower - The maker of solar panels declined after forecasting a lower-than-expected 2015 profit.
King Digital Entertainment - The mobile-game maker rose after Cowen offered upbeat comments about fourth-quarter ad revenue.
Alibaba Group Holding - China's electronic-commerce giant fell after saying it was readying its first bond sale.
Alamo Group - The seller of agricultural and construction equipment declined after pricing a public offering of 1.7 million shares.
Tyco International - The maker of safety products dropped after posting weaker-than-expected fourth-quarter revenue.
Bristol-Myers Squibb - The drug maker fell after Morgan Stanley downgraded its shares to equal weight from overweight.
Broadcom - The maker of semiconductors rose after Goldman Sachs upgraded it to buy from neutral.
Cyber-Ark Software - The information-security company surged after tally third-quarter earnings that topped expectations.
Churchill Downs - The racetrack operator declined after saying it would buy mobile-gaming company Big Fish Games for up to $885 million.
Navient - The student loan servicing company climbed after saying it would buy a portfolio of federally guaranteed student loans from Wells Fargo.