Pilgrim's Pride confirmed a revised proposal to buy Hillshire Brands for $55 a share, an offer that values the company at $7.7 billion. The offer came after Tyson Foods offered to buy Hillshire for $6.3 billion last week. Hillshire said it would conduct talks with both parties.
AT&T lifted its full-year revenue guidance, due in part to strong trends in its wireless business.
Among earnings, Dollar General posted earnings that missed by a penny, with revenue also short of consensus, citing poor winter weather and a competitive environment, among other factors.
Krispy Kreme slumped in premarket trading after the doughnut maker missed quarterly sales and cut its full-year earnings guidance.
And Quiksilver plunged sharply after the teen apparel retailer posted a wider-than-expected loss. (Click here for CNBC's full earnings coverage)
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Overnight, an HSBC survey showed that China's factory sector put in its best performance in four months in May as export orders rebounded, although activity remained in contraction territory.
European and Asian shares failed to rise on the news, which was already priced in following Monday's positive official manufacturing data from China.
Traders in Europe remain cautious ahead of Thursday's European Central Bank Governing Council meeting. Many economists expect President Mario Draghi to announce policy measures to combat low inflation, such as interest rate cuts, cheap loans to banks or even Federal Reserve-style asset purchases.
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In addition, President Barack Obama will begin his European trip with meetings in Poland to discuss security issues regarding Russia. Obama is also expected to meet with Ukrainian President-elect Petro Poroshenko.