Check out which companies are making headlines after the bell Wednesday:
Tesla - The maker of electric cars posted earnings per share of 33 cents, excluding one-time items, on revenue of $761 million, topping expectations for 21 cents a share on revenue of $686 million. Tesla said it sold a record 6,892 Model S vehicles in the fourth quarter and expects to deliver more than 35,000 vehicles in 2014. Shares spiked sharply in extended-hours trading.
(Read more: Stocks close near session lows, Nasdaq snaps 8-day win streak)
Facebook - The social-media giant will acquire WhatsApp messenger service for a total of approximately $16 billion, including $4 billion in cash and approximately $12 billion worth of Facebook shares. Shares slipped in extended-hours trading.
Safeway - The supermarket chain reported EPS of 53 cents on revenue of $11.3 billion, versus expectations for 48 cents a share on sales of $11.49 billion. In addition, It said it is in talks about possibly selling the company, but no deal has been reached. Shares rallied in extended-hours trading.
Marriott - The hotel group posted EPS of 49 cents, matching expectations, on revenue of $3.22 billion, missing estimates for $3.31 billion. The company also handed in current-quarter profit guidance that easily topped forecasts. Shares edged higher in extended-hours trading.
Jack In The Box - The fast food chain reported EPS of 75 cents on revenue of $450 million, topping forecasts for 66 cents a share on revenue of $435 million. In addition, the company said it expects to hand in full-year EPS of between $2.20 and $2.35, excluding items, against current expectations for $2.25. Shares gained in extended-hours trading.
Allstate - The insurer lifted its quarterly dividend by 12 percent, to 28 cents a share, and announced a $2.5 billion stock buyback program. Shares edged higher in extended-hours trading.
Merck - Several consumer and health-care companies, including Bayer and Novartis, are exploring a deal for Merck's consumer health-care business, according to Reuters, citing sources familiar with the matter. Merck shares gained in extended-hours trading.
Boeing - Drexel Hamilton assumed coverage of the Dow component with a hold rating. The brokerage's prior rating was a buy with a target of $130. Shares ticked higher in extended-hours trading.
W. R. Berkley - The financial services company increased its share repurchase authorization to 10 million shares. The stock gained in extended-hours trading.
Express - Janney Capital initiated coverage of the retailer with a neutral rating and a $20 price target. Shares were unchanged in extended-hours trading.
—By CNBC's JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC)
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