Stocks making the biggest moves midday: Nomura, ViacomCBS, Boeing and more

The ViacomCBS logo is displayed on the Nasdaq MarketSite to celebrate the company's merger, in New York, December 5, 2019.
Brendan McDermid | Reuters

Here are the stocks making headlines on Wall Street.

Nomura, Credit Suisse – Shares of both banks fell after they warned investors of significant hits caused by the forced liquidation of stock positions held by a U.S. hedge fund. CNBC and other outlets have reported that the fund is Archegos Capital Management, a multibillion dollar family office run by Bill Hwang. Nomura's U.S.-traded stock dropped more than 14%, while Credit Suisse shed 11.5%.

ViacomCBS, Discovery – The media companies' shares continued to fall following reports from CNBC and others that Archegos Capital Management was forced to liquidate its positions in the companies. The class B shares of ViacomCBS dropped 6.7% on Monday, while Discovery's class A shares fell 1.6%.

Kratos Defense & Security Solutions – Shares of the defense company rose more than 5% following news that Ark Invest's new space ETF will start trading on Tuesday with Kratos as a top holding. Ark's CEO and chief investment officer Cathie Wood has garnered popularity amid her flagship ETF's 150% return in 2020. Other constituents like L3Harris rose. Lockheed Martin and Boeing each rose about 2%.

Boeing – Shares of the aircraft maker gained more than 2%, becoming the biggest outperformer in the Dow Jones Industrial Average in midday trading. The advance came after news that Southwest Airlines had added 100 orders for the airliner's 737 Max jet. The first 30 jets are scheduled for delivery in 2022.

Twitter – Shares of the social media company advanced 2.7% after Truist upgraded the stock to a buy rating. The firm said that "tangible progress on product and tech platform" will driver "greater traction with users and advertisers." The firm also lifted its price target on the stock to $74, up from a prior target of $64. The new target is about 18% above where shares traded on Monday.

Facebook – The social media stock added 2.8% after Deutsche Bank hiked its price target to $385 per share from $355. The firm said in a note to client that it is growing more optimistic about Facebook's advertising business in 2021.

– CNBC's Maggie Fitzgerald, Yun Li and Pippa Stevens contributed to this report.