U.S. equities lost ground at midday to start the shortened trading week, as tech stocks fell. The Dow, S&P 500, and Nasdaq were all lower.

United Airlines (UAL) shares tumbled after the Federal Aviation Administration said regulators were increasing oversight of the carrier following a string of recent safety incidents.

Shares of Intel (INTC) and Microsoft (MSFT) slipped following a report that China is enforcing new restrictions on government purchases of chips and operating systems by foreign companies as it tries to boost its domestic tech sector.

Shares of Apple (AAPL), Meta Platforms (META), and Alphabet (GOOGL) fell as European regulators announced an investigation of the tech giants over whether changes they made to comply with the Digital Markets Act (DMA) were enough to meet the new law's requirements.

Super Micro Computer (SMCI) shares took off as JPMorgan initiated coverage with an “overweight” rating and price target of $1,150, calling SMCI the "leading company in the AI compute market."

Boeing (BA) shares advanced after the aircraft maker announced CEO Dave Calhoun and chair Larry Kellner would step down as Boeing faces production and quality issues that have led to investigations and a steep decline in its stock price.

Oil and gold futures were up. The yield on the 10-year Treasury note advanced. The U.S. dollar fell versus the euro, pound, and yen. Prices for most major cryptocurrencies made strong gains.