• Luigi Mangione was charged with the murder of UnitedHealthcare CEO Brian Thompson.
• Nvidia shares slumped after a regulator in China said it was investigating the chipmaker over possible violations of the country's antimonopoly law.
• Tesla is being sued by the family of a driver who died in a 2023 collision over its Autopilot technology.

Here are five key things investors need to know to start the trading day:

1. A step back

Stock futures changed little Tuesday morning after the S&P 500 and Nasdaq Composite both slid about 0.6% Monday. S&P 500 futures hovered near the flatline while Nasdaq 100 futures grew 0.05%, and futures tied to the Dow Jones Industrial Average dropped 0.02%. Follow live market updates.

2. CEO shooting suspect charged

Prosecutors in New York charged Ivy League grad Luigi Mangione on Monday with the murder of UnitedHealthcare CEO Brian Thompson, court records showed. Mangione was charged with second-degree murder, criminal possession of a loaded firearm, possession of a silencer, and possession of a forged instrument in state court in Manhattan, according to a court record. The suspect was detained by police in Altoona, Pennsylvania Monday morning after officers confronted him at a McDonald's and found a pistol, a silencer and seven 9mm full metal jacket rounds, multiple fake IDs and a U.S. passport in his backpack, authorities said.

3. Oracle's grim forecast

Oracle shares fell 7% in extended trading on Monday after the database software company reported fiscal second-quarter results that fell short of analysts' estimates. Oracle also issued a weaker-than-expected forecast. Second-quarter sales grew 9% year over year, and its cloud services business rose 12% from a year earlier to $10.81 billion, accounting for 77% of the company's total revenue. Oracle had previously raised its fiscal 2026 revenue guidance to $66 billion, about $1.5 billion more than what analysts projected.

4. Nvidia takes a hit

Nvidia shares ended Monday lower by about 2.6% after a regulator in China said it was investigating the chipmaker over possible violations of the country's antimonopoly law. The State Administration for Market Regulation opened an investigation into the chipmaker in relation to its acquisition of Mellanox, the Chinese government said Monday. Nvidia acquired the Israeli technology company that creates network solutions for data centers and servers in 2020. The news comes after the Biden administration announced a final round of curbs targeting semiconductor toolmakers last week. Trade tensions have also increased in anticipation of President-elect Donald Trump's proposed tariffs on foreign goods.

5. Tesla sued over Autopilot

The family of a Tesla driver who died in a 2023 collision is suing the EV maker, claiming that Tesla's
"fraudulent misrepresentation" its Autopilot technology was to blame. The incident involved a 2021 Model S, which crashed into a parked fire truck while the driver was using Tesla's Autopilot, a partially automated driving system. The family sued Tesla in October in Contra Costa County, California, but Tesla has since had the case moved from state court to federal court in California's Northern District. Plaintiffs generally face a higher burden of proof in federal court for fraud claims.

— CNBC's Brian Evans, Dan Mangan, Jonathan Vanian, Samantha Subin and Lora Kolodny contributed to this report.