Check out the companies making headlines in midday trading.

Biogen — Shares of Biogen slid more than 7% after Samsung denied a report in South Korean media that it was in talks to buy Biogen. The biotechnology stock had surged 9.5% on Wednesday on the report.

DiDi Global — The stock jumped 5.6% despite the company reporting a 1.7% decline in third-quarter revenue and a loss of $4.7 billion. Investors bought the dip in the Chinese ride-hailing company, which slid 8.2% Wednesday. It has also seen declines in 12 of the last 15 trading days.

RR Donnelley & Sons — The commercial printing stock rose nearly 5% after the company received a non-binding acquisition proposal at $11 per share in cash. The unsolicited offer comes two weeks after R.R. Donnelley agreed to be bought by affiliates of Chatham Asset Management, its largest shareholder, for $10.85 per share.

Virgin Galactic — Shares of the space travel company rose 6% as Virgin Orbit, its satellite-launching spin-off, geared up to begin trading Thursday on the Nasdaq, following an approved merger earlier this week with the blank-check company NextGen Acquisition Corp.

Micron Technology — The semiconductor stock dipped 1.3% after the company warned of production delays due to new Covid shutdowns in Xi’an, China. Micron said in a blog post that additional restrictions by the local government “may be increasingly difficult to mitigate.”

Kanzhun — The platform for job seekers saw its shares jump 13% after Jefferies initiated coverage of the stock with a buy rating and a $44 price target, implying upside of about 38% from its closing price Wednesday.

ViacomCBS — Shares of the media giant rose 3.6% and were among the top gainers in the S&P 500 on Thursday. The rise followed a Financial Times report Wednesday that U.S. video streamers are set to spend $115 billion on content in 2022. Discovery shares gained 3%, while Netflix and Fox rose about 1%. Apple and Disney were slightly higher as well.

 — CNBC’s Hannah Miao and Jesse Pound contributed reporting