Markit's final services sector PMI for May follows at 9:45 a.m. ET and at 10 a.m. the Conference Board's measure of consumer confidence is due. Economists in a consensus survey expect the consumer confidence index to rise to 83 in May, up from 82.3 in the prior month.
Pfizer edged up in premarket trading a day after the drugmaker walked away from its $116 billion bid to acquire AstraZeneca. AstraZeneca shares dropped.
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Hillshire Brands spiked more than 20 percent after the packaged food company was offered to be bought by poultry producer Pilgrim's Pride in a deal valued at $6.4 billion. Shares of Pinnacle Foods, which is in the process of being acquired by Hillshire, fell.
Over the weekend, the Financial Times reported that Apple will announce a software platform for its iPhone that will control home appliances. The announcement is expected at the company's Worldwide Developer Conference, which begins June 2.