Stocks making the biggest moves premarket: Vroom, Poshmark, Revolve, Green Plains and more

Check out the companies making headlines before the bell:

Poshmark — Shares spiked more than 5% after Barclays upgraded the online fashion retailer to overweight from equal weight. Poshmark will get a boost from the fast-growing second-hand clothing marketplace, especially if consumers trade down in a recession, Barclays said.

Vroom — Shares dropped more than 3% after JPMorgan downgraded the stock to underweight from neutral, saying that the online used car retailer will continue to see challenges amid a broader economic slowdown. Vroom has already plunged 80% this year.

Revolve — The stock fell more than 2% following a downgrade to underweight from equal weight from Barclays. The investment firm cited slowing revenue growth and tough comparisons at the clothing store company.

Green Plains — Green Plains declined more than 3% after Bank of America downgraded the stock to neutral from buy. The investment firm said the current valuation for the ethanol fuel producer is fair.

TaskUs — The outsourcing company for content moderation is facing near-term macro challenges, according to Morgan Stanley. The investment firm downgraded the stock to equal weight from overweight. Shares fell 3%.

Baidu, Alibaba, Pinduoduo — Shares of Chinese internet companies declined following weak economic data from China. Baidu, Alibaba and Pinduoduo each dropped more than 1%.

Comcast, Charter Communications — Shares of both broadband companies declined more than 1% following downgrades to neutral from Atlantic Equities. The firm cited worse-than-expected broadband results from both companies.

Dollar General — Shares of the discount retailer have fully priced in recession expectations, according to a Monday note from BMO Capital Markets. The firm downgraded Dollar General to market perform from outperform. The stock declined 1%.

Disclosure: Comcast is the owner of NBCUniversal, parent company of CNBC.