Check out which companies are making headlines after the bell Tuesday:
Twitter - The social media company posted earnings that broke even, on revenue of $250 million, exceeding Wall Street estimates for a loss of 3 cents a share on sales of $241 million. Still, shares dropped in extended-hours trading as the company's net loss grew by more than $100 million in the first quarter. The company also said it expects to post second-quarter revenue of between $270 million and $280 million, versus $273 million. Meanwhile, Twitter handed in full-year revenue guidance of between $1.2 billion and $1.25 billion, versus estimates for $1.24 billion.
eBay - The online auctioneer posted earnings of 70 cents a share on sales of $4.26 billion, topping estimates for 67 cents a share on sales of $4.23 billion. But shares declined in extended-hours trading as the company forecast current-quarter earnings of between 67 cents a share and 69 cents a share, less than the 70 cents a share expected by analysts.
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General Electric - Alstom's board has accepted GE's 10 billion euro offer for the company's energy division, according to French daily Le Figaro. Alstom is expected to issue a statement Wednesday, at around 7 a.m. ET. GE shares were largely unchanged in extended-hours trading.
Costco - The warehouse club increased its quarterly dividend by 14.5 percent to 35.5 cents a share from 31 cents a share. Shares were slightly lower in extended-hours trading.
Seagate - The data storage company posted earnings of $1.34 a share, excluding one-time items, on sales of $3.41 billion. Analysts expected the company to post earnings of $1.25 a share on sales of $3.42 billion. Shares gained in extended-hours trading.
Vistaprint - The company posted earnings of 24 cents a share on revenue of $286 million, widely missing estimates for 59 cents a share on sales of $311 million. Shares were hammered in extended-hours trading.
Panera Bread - The fast-casual restaurant chain posted earnings of $1.55 a share on sales of $605 million, topping expectations for $1.52 a share on sales of $597 million. But the company handed in current-quarter earnings outlook that fell short of expectations. Shares declined in extended-hours trading.
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Wells Fargo - The bank increased its quarterly dividend by 17 percent to 35 cents a share from 30 cents a share, as expected. The dividend increase was part of the company's 2014 Capital Plan that the Federal Reserve approved in March. Shares were slightly higher in extended-hours trading.
Lam Research - The semiconductor company announced a $1 billion capital return program and said it plans to initiate a quarterly dividend of 18 cents a share. Shares were higher in extended-hours trading.
Michael Kors - The clothier was initiated with a "buy" rating at Janney Capital with a $121 price target. Shares were largely unchanged in extended-hours trading.
—By CNBC's JeeYeon Park
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