Check out which companies are making headlines before the bell:
Fiat Chrysler Automobiles (FCAU)—The stock makes its Wall Street debut today, marking the return of a Chrysler-related stock to the U.S. market. Chrysler traded under its own name until 1998, when it was sold to Mercedes parent Daimler. It was then sold to Cerberus Capital Management in 2007, followed by a 2009 bankruptcy filing and Fiat's first purchase of a stake in 2011.
Danaher —The company will combine its communications business with NetScout in a tax-free transaction. Danaher shareholders will receive about 60 percent of NetScout's shares once the transaction is complete.
J.C. Penney—The retailer's shares were downgraded to "sell" from "neutral" at UBS, which said the company's earnings targets were too optimistic and that Penney is not debuting enough new merchandise.
Johnson Controls–The auto parts maker's stock was cut from "top pick" to "outperform" at RBC Capital, citing a lull in the company's portfolio transition.
Darden Restaurants–The Olive Garden parent was downgraded to "neutral" from "overweight" at Piper Jaffray, following the overhaul of the company's board on Friday and potential management changes.
T-Mobile US–The mobile operator's stock was upgraded to "outperform" from "neutral" at Macquarie, which cited strong fundamentals as well as valuation following a recent slide.
Sears Holdings–The retailer's Kmart unit was hit by a payment systems breach in September, and that some credit and debit card numbers were likely taken, though the company could not say how many. The breach did not affect customers of the Sears chain.
CSX – The rail operator declined comment on a Wall Street Journal report that it's been approached by Canadian Pacific Railway about a possible merger.
Comcast–The conglomerate's Universal Parks unit will open a $3.3 billion theme park in Beijing. The parent of NBCUniversal and CNBC received government approval for a 300-acre park that will be co-owned by Universal and four state-owned companies.
Steris—Steris is buying Britain's Synergy Health for $1.9 billion in cash and stock. Steris, an Ohio-based medical technology provider, will relocate its headquarters to Britain in another so-called "inversion" deal.
General Electric–GE is in talks for an acquisition of Milestone Aviation Group, according to the Wall Street Journal. The paper said GE's finance arm could purchase the helicopter-leasing company for more than $2.5 billion.
—By CNBC's Peter Schacknow
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