Check out the companies making headlines before the bell:
Macy's — The retailer reported adjusted earnings per share of 27 cents, well above the expected 14 cents a share. The company's same-store sales also grew for a fourth straight quarter and Macy's raised its earnings guidance for the year.
Tencent — Tencent reported better-than-expected earnings for the third quarter, boosted by strong growth from its gaming and social media group. On a year-over-year basis, net profit rose 30 percent at Tencent, while revenue grew by 24 percent.
Snap — The social media company has been subpoenaed by the Justice Department and Securities and Exchange Commission for information about its IPO in March of last year. This follows a shareholder lawsuit that alleges Snap misled people about how competition from Instagram had impacted the company.
Tilray — The marijuana producer reported a smaller-than-expected loss for the quarter and an 85 percent growth in revenue. Still, the stock fell nearly 5 percent in the premarket.
Apple — Guggenheim downgraded shares of the tech giant to "neutral" from "buy" and removed its price target of $245, noting iPhone sales could decline by 5 percent in 2019. The analyst also noted that higher average selling prices for the new iPhones will likely lead to "a period of digestion" for consumers.
Kellogg — Shares of Kellogg were downgraded to "neutral" from "overweight" by a J.P. Morgan analyst. The analyst also cut his price target to $66 a share from $73, and reduced his earnings estimates for the company. "Maintaining an Overweight rating in the face of flat EBIT growth in both 2018 and 2019 (and likely negative EPS growth in 2019) requires a bit more patience than we have at the moment," the analyst said in a note.
Conagra — Bernstein downgraded Conagra's stock to "underperform" from "market perform," highlighting a slowdown in sales of frozen entrees. "The frozen category has experienced positive growth over the past year … but this now seems to be running out of steam. Although consumer takeaway remains positive and is still strong on a 2-year basis, comparables become tougher from here," Bernstein said.
Boeing — Both the Federal Aviation Administration and Boeing are looking into possible software changes for the 737 MAX airplane after last month's Lion Air crash in Indonesia.
Blue Apron — The company said it will reduce its workforce by 4 percent as it tries to become profitable in 2019.