Stocks from the Reddit-forum frenzy are back on the move, with AMC Entertainment, Blackberry and Koss all up premarket. Here’s what we’re watching before Wednesday’s trading gets underway.

  • Joke cryptocurrency Dogecoin has jumped nearly 28% from its 5 p.m. ET price after Coinbase said it would allow users to trade it on a platform that is geared toward more experienced investors.
  • The meme stocks are back. AMC Entertainment has already been on a tear recently, and is up another 20% premarket. Other shares popular among retail investors were also climbing, with BlackBerry up 15%, Koss up 6.9%—and perhaps the flagship stock for the Reddit crowd, GameStop, up a relatively meager 0.8%.
  • Shares of Samsung Publishing, which owns a stake in the producer of “Baby Shark,” climbed 6% in South Korean trading Wednesday after Elon Musk tweeted the viral children’s song with a note saying “Baby Shark crushes all! More views than humans.”
  • U.S. stock futures edged up 0.2%, suggesting muted moves for major indexes at the opening bell as investors awaited fresh insights on the economic rebound and rising inflation. Read our full market wrap here.
What’s Coming Up
Market Movers to Watch
  • Constellation Pharmaceuticals soared 67% premarket. The biopharmaceutical company is being acquired by MorphoSys for $34 a share in cash. Constellation’s stock closed on Tuesday at $20.24.
  • Zoom Video shares gained 1.8% ahead of the bell. The group-video chat provider’s customer count rose sharply and revenue almost tripled in the recent quarter, signaling the tech darling of the pandemic era is enjoying robust customer growth as offices open back up.
A sign for Zoom Video Communications ahead of the company’s Nasdaq IPO in New York.

A sign for Zoom Video Communications ahead of the company’s Nasdaq IPO in New York.

Photo: Mark Lennihan/Associated Press

  • StoneCo shares dropped 2.5% premarket. The financial technology company reported quarterly results after Tuesday’s close and said it had increased its headcount and its investments in marketing.
  • Hewlett Packard Enterprise slipped 0.9% premarket, even after the company again raised annual financial projections following a stronger-than-expected performance in the latest period.
  • Ambarella shares added 3.4% premarket. The maker of semiconductors that offer artificial-intelligence processing and other features reported better sales and a narrower loss for its latest quarter despite a range of supply chain disruptions.
  • Shares of online marketplace Etsy inched up 1.2% premarket. It agreed to buy Depop, a privately held fashion marketplace, for $1.625 billion, consisting mainly of cash.
Market Facts
  • The Chinese yuan is at its strongest level since 2018, at around 6.37 to the U.S. dollar. The currency only needs to rise by a little over 5% to hit a new historical high. It has rallied by almost 12% in the last year already.
  • AMC Entertainment took advantage of a skyrocketing stock price last week to sell shares to a hedge fund for $230.5 million, it disclosed Tuesday, news that drove its stock higher still. Its share price jumped 23% on Tuesday and is up more than 1,400% for the year, including a furious 116% climb last week.
  • On this day in 1997, under orders from the U.S. Department of Justice and the Securities and Exchange Commission, Nasdaq reduced the minimum “tick size,” or trading increment, from 1/8 to 1/16 on all stocks with a bid price of $10 or more.
Chart of the Day
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Corrections & Amplifications
StoneCo Ltd. reported quarterly earnings after markets closed on Tuesday, June 1, 2021. An earlier version of this article incorrectly said it had reported on Thursday. Corrected on June 2.

Write to James Willhite at james.willhite@wsj.com