Stocks making the biggest moves premarket: Uber, DoorDash, Spirit, Altria and more

Check out the companies making headlines before the bell:

Uber (UBER), DoorDash (DASH) – Uber fell 3.1% in the premarket while DoorDash tumbled 7.5%, following the news that Amazon (AMZN) struck a deal to add membership in rival food delivery service Grubhub as a free benefit for its "Prime" members. Amazon's deal also gives it the option to take a stake in Grubhub.

Spirit Airlines (SAVE) – Spirit won the right to operate peak-hour afternoon and evening flights at Newark-Liberty International Airport. Spirit had been trying to win the slots that Southwest Airlines (LUV) vacated when it stopped operating at Newark in 2019, but the FAA initially opted not to award them while it assessed traffic conditions at the airport.

Altria (MO) – Altria gained 2.7% in the premarket after the FDA temporarily suspended its ban on Juul e-cigarette products. Altria has a 35% stake in Juul, which will be allowed to keep its products on the market while it appeals the FDA's ban.

Coinbase Global (COIN) – Coinbase was downgraded to "neutral" from "overweight" at Atlantic Equities, which cites a number of factors including questions about the cryptocurrency exchange operator's ability to attract talent. Coinbase fell 3.3% in premarket trading.

Rocket Companies (RKT) – Rocket Companies rallied 4.4% in premarket trading after Wells Fargo Securities upgraded the fintech company's stock to "overweight" from "equal weight." Rocket shares have fallen about 41% so far this year.

Sempra Energy (SRE) – Sempra Energy was upgraded to "buy" from "neutral" at Goldman Sachs, which feels the energy company's stock is undervalued after falling more than 9% over the past month.

Resolute Forest Products (RFP) – The paper and wood products maker agreed to be acquired by Montreal-based paper products producer Paper Excellence Group for $20.50 per share, plus a contingent value right. Resolute Forest Products soared 66.8% in premarket action.

Kornit Digital (KRNT) – The Israel-based developer of digital printing technologies for the apparel industry saw its stock tumble 24.3% in the premarket. That came after Kornit slashed its current-quarter guidance almost in half and said the third quarter may see a similar slowdown, due to a pullback in e-commerce following the pandemic-induced surge.