Check out which companies are making headlines before the bell:
Merck — The drugmaker earned an adjusted 89 cents per share for the first quarter, 4 cents a share above estimates, although revenue was short of forecasts. Merck did see a negative impact from currency fluctuations, as well as a drop in sales of rheumatoid arthritis drug Remicade.
Alibaba — The China-based online retail giant saw earnings miss forecasts, but revenue did beat analyst projections and Alibaba also saw increases in the key metric of gross merchandise volume.
Limited Brands — The Victoria's Secret parent reported a 1 percent rise in comparable store sales for April, below the consensus estimate of a 4.8 percent increase.
Time Inc. — The publisher lost an adjusted 11 cents per share for its latest quarter, 3 cents a share less than expected. Its revenue exceeded Street forecasts. Time's results were helped by increases in digital advertising and by contributions from acquisitions.
Becton Dickinson — The medical products maker beat estimates by 16 cents a share, with adjusted quarterly profit of $2.18 per share. Revenue was essentially in line with expectations. The company also raised its full-year forecast.
Avon Products — The cosmetics company posted a surprise loss of seven cents per share; analysts expected a 2 cents a share profit. Revenue was very slightly above forecasts, but the company struggled to boost growth in some key overseas markets like Brazil and China.
Discovery Communications — The media company beat estimates by 2 cents a share, with quarterly profit of 42 cents per share. Revenue was in line with forecasts. The company cited strong viewership on a variety of platforms as factors contributing to its latest results.
AmerisourceBergen — The drug distributor earned an adjusted $1.68 per share for its latest quarter, 9 cents a share above estimates. Revenue was just below forecasts. AmerisourceBergen also cut its full-year forecast, with generic drug pricing pressure a key factor. The company did announce an extension of its distribution contract with Walgreens Boots, its biggest retail pharmacy customer.
Tesla — The automaker reported a quarterly loss of 57 cents per share, 1 cent smaller than expected, with revenue matching estimates. Tesla also said it was accelerating its production targets, now aiming to deliver 500,000 vehicles annually by 2018. The company had long said it would achieve that goal by 2020.
Whole Foods Market — Whole Foods beat estimates by 3 cents a share, with quarterly profit of 44 cents per share. Revenue came in marginally below forecasts. The organic grocery chain did cut its full-year profit and sales forecast, amid increasing competition and promotional activity.
Fitbit — Fitbit came in 7 cents a share above estimates, with adjusted quarterly earnings of 10 cents per share. The maker of wearable fitness devices also saw revenue beat forecasts. However, its current-quarter forecast is weaker than expected, as it spends money to promote new offerings like its Blaze smartwatch and Alta wrist band.
21st Century Fox — Fox matched estimates with adjusted quarterly profit of 47 cents per share, and the media company's revenue beat Street forecasts. Fox's results were helped by a rise in ad sales and affiliate fees.
Zynga — Zynga broke even on an adjusted basis for its latest quarter, compared to forecasts of a 1-cent-per-share loss. The online game maker saw revenue beat estimates on increased ad sales, although its customer base did decline.
TripAdvisor — TripAdvisor earned an adjusted 32 cents per share for its latest quarter, 14 cents a share below estimates. Its revenue also missed estimates. The travel website did see more hotel bookings on its website, but that impacted revenue from referrals to other travel sites.
Kraft Heinz — The company reported quarterly profit of 73 cents per share, 11 cents a share above estimates. The food maker's revenue also came in above analysts' forecasts. The company saw costs fall during the quarter, as well as seeing increased sales for its condiment and sauce products.
MetLife — MetLife missed estimates by 18 cents a share, with adjusted quarterly profit of $1.20 per share. The insurer's revenue fell short of Street estimates, as well. MetLife saw lower returns on its various investments, as well as higher expenses.
Weight Watchers — Weight Watchers lost 1-cent-per- share less than expected at 17 cents per share, although revenue for its latest quarter was below forecasts. The weight management company did raise its full-year forecast on a boost in subscriber numbers, as well as meeting attendance.
Caterpillar — Caterpillar shares are under pressure after Greenlight's David Einhorn revealed a short position in the heavy equipment maker at the Sohn Conference.
Anheuser Busch Inbev — The company's $100 billion deal to buy SABMiller was cleared by Australian antitrust regulators. The beer brewer still needs clearance in Europe to proceed with the transaction.