Check out the companies making headlines before the bell:

UnitedHealth — The health insurer reported adjusted quarterly profit of $3.73 per share, beating the consensus estimate of $3.60. Revenue beat forecasts, and the company also raised its full year forecast amid strength in its Optum health information technology unit as well as increases in health plan memberships.

Johnson & Johnson — Johnson & Johnson beat estimates by seven cents with adjusted quarterly profit of $2.10 per share, with revenue also beating forecasts. Results were helped by strong sales of treatments for psoriasis, Crohn's disease, and cancer, and J&J has now raised its full-year sales forecast.

Bank of America — The bank earned 70 cents per share for the first quarter, 4 cents a share above estimates. Revenue came in slightly below forecasts, amid what CEO Brian Moynihan called a "challenging" capital markets environment.

BlackRock — The asset management firm beat earned $6.61 per share for the first quarter, compared to a consensus estimate of $6.13 a share. Revenue was in line with Wall Street forecasts, and BlackRock also announced a 5% dividend increase.

Netflix — Netflix was upgraded to "buy" from "hold" at Deutsche Bank, based on valuation and consensus subscriber estimates that the bank considers conservative.

AT&T — AT&T sold its ownership stake in Hulu to the video streaming service for $1.43 billion, a sale that values Hulu at $15 billion. That leaves Walt Disney and NBCUniversal and CNBC parent Comcast as Hulu's owners, with Disney owning 60%.

J.B. Hunt Transportation Services — J.B. Hunt reported quarterly profit of $1.09 per share, missing the $1.26 a share consensus estimate. The trucking and logistics company's revenue was short of forecasts as well, as its volumes were hurt by severe weather conditions in the Midwest.

Chevron — Chevron won a court victory in a case involving Ecuador's attempt to collect a $9.5 billion judgment against the energy giant over pollution. The Supreme Court of the Netherlands ruled against Ecuador's attempt to overturn an international tribunal ruling in Chevron's favor.

Goldman Sachs — Goldman will lay off 98 employees in New York, according to a filing with New York State. The filing said the workers are being dismissed for economic reasons, but did not specify where the layoffs would occur within the bank.

Amgen — Amgen set a list price of $1,825 per month for its Evenity osteoporosis drug. The Food and Drug Administration approved the drug last week, but mandated a so-called "black box" warning about an increased risk of heart attack and stroke.

Walmart — Walmart announced a partnership with children's styling service Kidbox, and will offer fashion boxes for kids containing five items for $48. That represents a 50 percent discount off suggested retail prices for the items.

DowDupont — DowDupont was downgraded to "sector perform" from "top pick" at RBC Capital Markets, which points to macroeconomic concerns for the chemical maker.

Western Digital — Western Digital was upgraded to "buy" 'from "hold" at Deutsche Bank, which cites favorable data points in both hard disk drives and NAND flash memory.