Check out which companies are making headlines before the bell:
St. Jude Medical — The stock is under pressure following a report by short seller Muddy Waters, which posted an alleged medical advisory on premature battery depletion in several St. Jude devices.
Alcoa — Alcoa posted earnings of 32 cents a share, missing analysts' estimates of 35 cents a share. Revenue also fell short of expectations. The report comes before Alcoa plans to split into two independent, publicly traded companies.
Yahoo — Verizon CEO Lowell McAdam told a California technology conference that his company had no plans to walk away from its planned acquisition of Yahoo's core internet assets. He did say it's possible that the $4.8 billion price tag could be renegotiated in the wake of the recently revealed massive 2014 Yahoo security breach.
Twitter — Twitter was upgraded to "hold" from "sell" at Evercore, which based its move on the recent plunge in the share price following reduced prospects for a Twitter sale.
ConAgra — The food producer's board approved a $1.25 billion stock buyback program, and also said the spin-off of its Lamb Weston unit would have a record date of November 1 and a distribution date of November 9.
Illumina — Illumina cut its revenue guidance because of a bigger-than-expected decline in sales of the company's gene sequencing tools.
UBS — UBS was among a handful of banks fined over alleged money laundering activities surrounding Malaysian sovereign investment fund 1MDB. Singapore's monetary authority also fined DBS (Development Bank of Singapore) and shutdown the Singapore operations of Switzerland's Falcon Private Bank.
Fiat Chrysler, Cummins — Fiat Chrysler and Cummins are at odds over the $200 million estimated cost of a recall involving 130,000 Dodge Ram pickup trucks equipped with Cummins-made diesel engines. The recall occurred because the engines may exceed U.S. pollution limits. The automaker has sued Cummins for the $60 million it has spent so fair repairing 42,000 of the trucks involved in the recall. Separately, Cummins was upgraded to "buy" from "neutral" and added to the "Conviction Buy" list at Goldman Sachs.
Apple — Apple remains a stock to watch on the mounting mobile phone problems suffered by competitor Samsung, which has now halted all production of Galaxy Note 7 phones amid reports that it may discontinue that model altogether.
Caterpillar — Caterpillar was upgraded to "buy" from "neutral" at Goldman Sachs, on optimism about further gains for the heavy equipment maker. Caterpillar is already the Dow industrial average's best year-to-date performer with a gain of nearly 30 percent. Goldman sees the potential for higher profit margins during the current business cycle.
Nike — Susquehanna Financial initiated coverage on the athletic footwear and apparel maker with a "positive" rating, saying a 16 percent pullback this year represents a rare opportunity to buy a "world class equity" in a business that's in a favorable cycle.
Seagate Technology — JPMorgan Chase upgraded the disk drive maker's stock to "neutral" from "underweight," owing to a slowing decline in sales of server drives as well as reduced exposure for Seagate to the personal computer market.
Twilio — The cloud computing company issued preliminary third quarter sales numbers that comes in above the Street's current forecast, helping the stock wipe out part of a Monday loss that followed news of a follow-on stock offering.