Check out the companies making headlines before the bell:

Amazon, Apple – Chinese equipment manufacturer Super Micro may have allowed microchips used for spying into data center equipment run in the U.S. by Amazon Web Services, Apple, and others, according to a Bloomberg BusinessWeek report. Apple, AWS and Super Micro dispute the report.

Walgreens Boots Alliance – The drugstore chain took a minority stake in Birchbox, a digital beauty subscription service. The two companies also formed a partnership, which will see a pilot program roll out across 11 Walgreens stores in a new attempt to appeal to millennials.

Toyota – The Japanese automaker announced it is forming a mobility services joint venture with tech giant Softbank. Beginning April 2019, the venture will use data to optimize supply and demand in the transportation space.

General Motors – When testing the four most popular automated driving systems, Consumer Reports said Cadillac's Super Cruise does the best job of ensuring the vehicle is driven safely while making sure drivers pay attention when they take their hands off the steering wheel.

Barnes & Noble – The retailer named a special committee to review bids for the company, as it said it has received "expressions of interest" from "multiple parties."

Facebook – A top European Union regulator opened a formal investigation into the data breach at Facebook that affected nearly 50 million accounts.

Snap – Citi lowered its price target on the struggling tech company to $7 a share. The firm cited five reasons, including a lack of "meaningful changes in revenue growth," Citi said.

Tilray – The cannabis company announced a plan to raise capital through $400 million of convertible senior notes.

Constellation Brands – The beverage maker reported second-quarter earnings of $2.87 a share, above the $2.61 a share expected by analysts surveyed by FactSet. Constellation also increased fiscal 2019 guidance to a range of $9.60 a share to $9.75 a share, from its previous estimate of $9.40 a share to $9.70 a share.