Stocks making the biggest moves premarket: Delta, Bed Bath & Beyond, Costco, GM & more

Check out the companies making headlines before the bell:

Delta Air Lines – The airline reported adjusted quarterly profit of $2.32 per share, beating the consensus estimate of $2.26 a share. Revenue was slightly below forecasts, but Delta's bottom line was helped by strong demand growth which prompted it to hire more pilots, flight attendants, and airport workers.

Bed Bath & Beyond – The housewares retailer named Target Chief Merchandising Officer Mark Tritton as its new chief executive officer, succeeding interim CEO Mary Winston. His appointment is effective November 4.

Costco – The retailer reported September comparable-store sales of 4.2%, exceeding the consensus estimate of 3.8%.

PG&E – The utility's shares are under pressure after a judge ruled that a rival bankruptcy plan from Elliott Management and other bondholders could be considered. The ruling stripped PG&E of an exclusive right to propose a chapter 11 recovery plan.

General Motors – GM reported a 17.5% decline in third-quarter China vehicle sales, hurt by the ongoing trade war, a slower economy, and increased competition.

T-Mobile US, Sprint – Mississippi dropped its legal challenge to the proposed $26.5 billion merger between the wireless carriers. That follows an agreement between the two sides which, among other things, will expand high-speed internet access to the state's rural areas.

UnitedHealth – The health insurer was downgraded to "hold" from "buy" at Jefferies, which points to tough competition from rival Anthem as well as policy uncertainty related to recent court rulings and the upcoming presidential election.

Cisco Systems – Cisco was downgraded to "neutral" from "buy" at Goldman Sachs, which is concerned about the impact of continuing weakness in enterprise spending on the networking equipment maker.

Apple – Apple was upgraded to "buy" from "neutral" at Longbow Research, which cited increased demand for updated iPhones.

Kroger – The supermarket chain's stock was downgraded to "hold" from "buy" at Jefferies, due to what the firm feels is a weak long-term strategy. Jefferies also said Kroger's venture into online grocery fulfillment is a costly, time-consuming venture.

Canopy Growth – The cannabis producer appointment Constellation Brands Chief Financial Officer David Klein as its board chairman. The spirits producer owns a 38% stake in Canopy.

Match Group – The owner of Tinder and other dating services was upgraded to "outperform" from "perform" at Oppenheimer, which points to lowered concerns over competition from Facebook.