Check out which companies are making headlines before the bell:
HCP — The health care real estate investment trust will spin off its HCR ManorCare portfolio into a separate, publicly traded REIT specializing in nursing and assisted living properties.
Lending Club — The online lending marketplace said its CEO Renaud Laplanche had resigned after the board determined he had violated the company's business practices. He'll be replaced on an interim basis by President Scott Sanborn.
Tyson Foods — Tyson earned an adjusted $1.07 per share for its latest quarter, with revenue also beating estimates. The beef and poultry producer said it was pleased with its results in what typically is the most challenging quarter of the year.
Southwest Airlines — The airline reported a 4.7 percent increase in revenue passenger miles in April compared to a year ago. Southwest also had a load factor of 83.4 percent, its highest ever for April.
Teva Pharmaceutical — The drugmaker earned an adjusted $1.36 per share for its latest quarter, beating estimates by 19 cents a share. Revenue also beat forecasts, with generics continuing to drive results despite no new introductions during the quarter.
Berkshire Hathaway — Warren Buffett's firm missed estimates on both the top and bottom lines. Buffett had warned at last weekend's annual meeting that a slump in shipments at the company's Burlington Northern Santa Fe railroad unit would drag down results.
Walt Disney — Disney's "Captain America: Civil War" topped the weekend box office with a very strong $181.8 million in North American ticket sales. That performance was the fifth-best domestic weekend opening of all time.
Twitter — Twitter has cut off U.S. intelligence agencies from its service that examines its entire output, according to The Wall Street Journal.
Facebook — Facebook won a court battle in China over its trademark, in a case involving a Chinese beverage company that owned the trademark "face book."
Tribune Publishing — The newspaper publisher adopted a shareholder rights plan, following its rejection of Gannett's roughly $400 million takeover bid. Tribune has been urged by Oaktree Capital, its second largest shareholder, to negotiate with Gannett about a possible takeover.
Depomed — The drugmaker may once again be a target of Horizon Pharma if Depomed is forced to put itself up for sale, according to the New York Post. Depomed successfully fought off a takeover bid from Horizon late last year.
General Electric — GE will seek more acquisitions in oil and gas after the failure of Halliburton-Baker Hughes merger removed an opportunity to buy assets. Chief Financial Officer Jeff Bornstein told Bloomberg that GE had been in talks for businesses the two oilfield services giants were planning to sell.