Check out the companies making headlines before the bell:

Dollar Tree — Dollar Tree matched Wall Street forecasts, with adjusted quarterly profit of $1.14 per share. Revenue was above forecasts, however, and the discount retailer saw same-store sales rise 2.2% compared to a consensus estimate of 2.1%. Dollar Tree also gave a weaker-than-expected full-year earnings forecast.

Dollar General — The discount retailer earned $1.48 per share for the first quarter, 9 cents a share above estimates. Revenue came in above forecasts as well, and a same-store sales increase of 3.8% beat the Refinitiv consensus of a 2.9% rise.

Movado — The watch maker reported adjusted quarterly profit of 24 cents per share, 7 cents a share below estimates. Revenue also missed forecasts and Movado said the retail environment remains challenging. The company also said economic uncertainty and currency volatility are potential headwinds, although it is optimistic about its prospects and reiterated its prior full-year forecast.

Express — The clothing retailer lost 15 cents per share, lower than the 31 cents a share loss that analysts had anticipated. Revenue beat forecasts, and a same-store sales decline of 9 % was less than the 10.1% consensus forecasts of analysts polled by Refinitiv.

Sanderson Farms — The poultry producer beat estimates by 18 cents a share, with quarterly profit of $1.83 per share. Revenue also beat consensus. Sanderson said a cold, wet spring in the U.S. has put upward pressure on prices.

PVH Corp. — PVH reported adjusted quarterly profit of $2.46 per share, beating estimates by a penny a share. The maker of the Calvin Klein and Tommy Hilfiger apparel brands saw revenue miss estimates, however, and also cut its full-year forecast as it absorbs the impact of higher China tariffs. PVH sources the majority of its offerings from China.

Comcast — Guggenheim Securities upgraded the parent of NBCUniversal and CNBC's stock to "buy" from "neutral," noting growth in the broadband business and saying that NBCU is operating at a very high level.

Palo Alto Networks — Palo Alto beat estimates by 6 cents a share, with adjusted quarterly profit of $1.31 per share. The cybersecurity company's revenue also topped Wall Street forecasts, however it gave a weaker-than-expected current-quarter forecast as acquisitions negatively impact its bottom line.

Twilio — Twilio announced a $750 million stock offering, with underwriters being given the option to sell an addition $112.5 million in shares in the cloud-computing company.

Invitation Homes — Blackstone sold more than $1 billion in shares of the single-family home landlord, launched by Blackstone after the financial crisis. The shares are now trading near a record high amid rising rents and strong demand.

Keysight Technologies — Keysight reported adjusted quarterly profit of $1.22 per share, beating the consensus estimate of 98 cents a share. The provider of electronics technology's revenue came in above Street forecasts, as well, as it saw growth in 5G and automotive markets. The company also issued an upbeat forecast.

Veeva Systems — Veeva beat estimates by 5 cents a share, with adjusted quarterly profit of 50 cents per share. Revenue also exceeded forecasts. Veeva is a provider of cloud software for the life sciences industry.

Citigroup — Citi was upgraded to "buy" from "neutral" at Goldman Sachs, which thinks the bank has a realistic path to growth in key metrics next year even without strengthening global growth or higher interest rates.

Verizon — Verizon was downgraded to "neutral" from "buy" at UBS, based on a valuation that it feels is in line with historical trends. UBS does say that Verizon is well-positioned as a defensive investment.