Southwest Airlines - The airline earned $0.09 per share, excluding certain items, one cent above estimates. However, it also saw higher operating expenses and a decline in passenger traffic.
Nokia - Nokia beat estimates with its latest quarterly earnings, but also announced plans to eliminate its dividend.
Apple - The stock is under pressure after a disappointing revenue forecast and falling short of iPhone sales expectations for the just-concluded quarter. Apple did earn $13.81 per share for its fiscal first quarter, which was above Street estimates of $13.47.
Amgen - Amgen earned $1.40 per share for the fourth quarter, two cents above estimates, with revenues also beating consensus. It's also issuing an upbeat forecast for 2013, with the biotech company saying it's on track to hit the upper end of its 2015 revenue forecast two years early.
Stryker - The company reported fourth quarter profit of $1.14 per share, two cents above estimates, on improving sales of its orthopedic implants. It also reiterated its prior full-year 2013 earnings guidance.
Western Digital - Western Digital earned $2.09 per share for its fiscal second quarter, beating estimates by 27 cents. Revenues were also above estimates, with the hard disk drive maker's results driven by growth in its enterprise segment.
SanDisk - The company trounced estimates for the fourth quarter with profit of $1.05 per share compared to estimates of $0.76. But the memory chipmaker's shares are coming under pressure because of a disappointing revenue outlook, driven by falling prices.
Symantec - Symantec is planning to lay off a significant number of managers and reorganize internally, according to a Reuters interview. But CEO Steve Bennett also says the security software maker has decided not to sell off any major assets.
Sony - Sony has been fined $396,000 by British regulators for insufficient security measures on its PlayStation Network. The fine stems from an April 2011 cyber attack that targeted the network.