Check out which companies are making headlines before the bell:
Delta Air Lines—The airline is increasing its quarterly dividend by 50 percent to 13½ cents per share, and has also announced a new $5 billion share repurchase program.
Humana—Sterne Agee downgraded the hospital operator to "underperform" from "neutral," citing material earnings guidance risk and a lower chance of the company being acquired than many investors think.
Owens-Illinois—The company is buying the food and beverage glass container business of Mexico's Vitro for $2.15 billion in cash. Vitro is the largest supplier of glass containers in Mexico.
Kimberly-Clark—Barclays upgraded the consumer products maker's stock to "overweight" from "equal weight," saying the stock is trading at a discount to its peers while performing at least equally as well.
Microsoft—Deutsche Bank upgraded Microsoft to "buy" from "hold," saying lower estimates and a slower PC market are already reflected in the stock, and that there's new investor enthusiasm about Office 365 and other products.
Cablevision—Reuters reports Cablevision will drop its bid to buy the New York Daily News for $1. The company reportedly feels even paying $1 is not justified because of the newspaper's poor financial condition.
American Express—The company raised its quarterly dividend to 29 cents per share from 26 cents, and announced it will buy back 150 million of its shares. That program replaces a prior authorization which still had 45 million shares remaining.
Vertex Pharmaceuticals—The drug maker got a positive FDA panel recommendation for its combination cystic fibrosis therapy known as Orkambi. The FDA usually follows the recommendations of its panels.
GoDaddy—The internet domain name registrar saw first quarter sales numbers beat expectations, and also issued upbeat guidance for the current quarter. GoDaddy has been benefiting from new customer growth and stronger demand for its newer applications for business.
McKesson—The drug distributor earned an adjusted $2.94 per share for its latest quarter, beating estimates of 20 cents, with the company's revenue essentially in line with forecasts. McKesson also expanded its share buyback program by $500 million.
Zillow—The real estate website operator reported profit of 5 cents per share, better than the consensus analyst forecast of an 11 cent per share loss. Revenue was also better than expected on improved ad sales, and Zillow also reported upbeat growth in its mobile business.
Toyota, Nissan, and Honda—The automakers have expanded their recalls of cars with air bags made by Takata. Toyota and Nissan said they would recall about 6.5 million cars around the world, while Honda did not give specific details. The Takata air bags have been plagued with problems related to their inflators.
UBS—The Justice Department could reverse its agreement not to prosecute the Swiss bank, according to Bloomberg. The original deal involved alleged manipulation of interest rates.
General Electric—The company is putting its Japan-based commercial finance unit up for sale, according to Dow Jones, a transaction that could fetch $5 billion.
Facebook—The social network will begin hosting articles from nine publishers on its mobile app beginning today.