Dresser-Rand —Germany's Siemens agreed to buy the oilfield equipment maker for $83 per share. Dresser-Rand closed Friday at $79.91, but had jumped last week on speculation that a deal with Siemens might be near.

Sigma-Aldrich –The life sciences company is being bought by Germany's Merck for $17.6 billion in cash , or $140 per share. That represents a 37 percent premium over Friday's closing price.

AutoZone –The auto parts retailer earned $11.28 per share for its fourth quarter, two cents above estimates, though revenue was slightly below forecasts. AutoZone registered a 2.1 percent increase in same-store sales for the quarter.

Check out which companies are making headlines before the bell:

Viasystems–The maker of circuit boards is being bought by rival TTM Technologies for about $368 million in cash and stock. The deal is worth a total of about $16.46 per Viasystems share, a nearly 41 percent premium over Friday's close.

BlackBerry–The smartphone maker is planning to sell its new Passport smartphone in the U.S. for $599 without subsidies, compared to $649 for the new iPhone 6 and $749 for the iPhone 6 Plus.

Walgreen–Barclays downgraded Walgreen to "equal-weight" from "overweight" at Barclays, following an analysis of the company's prospects over the next few years. The bank said the company's forward earnings guidance is not as conservative as it seemed at first.

TreeHouse Foods–SunTrust upgraded the food and beverage maker's stock to "buy" from "neutral", saying the company is positioned to meaningfully outpace its peers.

Alibaba–The China e-commerce company's Wall Street debut is now the biggest IPO in world history at $25 billion, with underwriters exercising their option to sell additional shares. Investors are watching shares of Yahoo as well, with the stock having been downgraded at both Bank of America Merrill Lynch (to "neutral" from "buy") and Bernstein (to "market perform" from "outperform). The search giant owns 22.5 percent of Alibaba and Bernstein notes the passing of the Alibaba IPO means more uncertainty for the prospect of improvement in Yahoo's stock price.

Bank of America–The bank's shares could jump 50 percent in the next three years, according to a report in this weekend's Barron's.

General Motors–GM is recalling nearly 222,000 vehicles to deal with a parking brake defect that could potentially cause a fire. The issue affects late model Cadillac XTS and Chevrolet Impala vehicles.

Microsoft–Microsoft has delayed the planned Tuesday launch of its Xbox One video game console in China, though Microsoft said the console would be out in that country by the end of the year. The company did not give a reason for the delay.

Google–The search giant picked HTC to build its planned 9-inch Nexus tablet, according to the Wall Street Journal.

Sears–The retailer failed to get any acceptable bids for its Sears Canada unit, according to the New York Post, after potential bidders examined the company's books.

EMC–The company held merger talks with both Dell and Hewlett-Packard, according to the WSJ, which said the data storage equipment maker is continuing to explore options.

—By CNBC's Peter Schacknow

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