• Nvidia became the most valuable public company in the world.
• Boeing's CEO went to Capitol Hill to defend the company as concerns about its safety and quality lapses grow.
• The S&P 500 and the Nasdaq Composite continued their run of record highs.

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

1. Hot streak

The S&P 500 spun up another record on Tuesday (which was the most recent trading day as markets were closed Wednesday for the Juneteenth holiday). The broad market index added 0.25%, while the Nasdaq Composite also hit another new high, inching up 0.03%. The Dow Jones Industrial Average, meanwhile, ticked up 56.76 points, or 0.15%. Nvidia was the star of the show yet again on Tuesday, climbing 3.5%. Looking ahead, investors will be watching for initial jobless claims figures and housing starts data on Thursday morning. Follow live market updates.

2. MVP

There's a new king of the stock market. Nvidia became the most valuable public company in the world on Tuesday as its market capital surpassed Microsoft's. Shares of the chipmaker climbed 3.5% for the day, giving the company a market cap of $3.34 trillion and pushing it above Microsoft's $3.32 trillion. Nvidia, credited as the engine behind an explosion in AI, has had a meteoric rise to the top of the stock market. Its shares are up more than 170% so far in 2024.

3. Tough Boeing

A Senate panel grilled Boeing CEO Dave Calhoun on Tuesday about the company's safety and quality lapses, allegations of corner-cutting from whistleblowers and Calhoun's own pay package. The planemaker's reputation has been tarnished since a midair door-panel blowout on an Alaska Airlines flight in January. The Senate subcommittee also released new whistleblower testimony from a quality-assurance investigator who said the company lost track of parts that were either damaged or not up to specification. Calhoun, who has said he would step down by the end of the year, testified that the company has heard concerns about its culture "loud and clear" and it is "taking action and making progress."

4. Darden earnings

Olive Garden's parent company Darden Restaurants on Thursday reported earnings that beat analysts' expectations, but revenue fell slightly short of forecasts. The company's fine-dining restaurants struggled more than analysts expected. Darden's net sales for the fiscal fourth quarter rose 6.8% to $2.96 billion, led by the company's acquisition of Ruth's Chris Steak House and 37 other net new locations. Shares of the restaurant chain company were up more than 1% in premarket trading.

5. New AI on the block

OpenAI co-founder Ilya Sutskever is launching a new artificial intelligence company. He's calling his new venture Safe Superintelligence, or SSI, and said in a post on X that he would continue to focus on safety. Sutskever was previously the chief scientist at OpenAI. He was one of several board members who clashed with OpenAI CEO Sam Altman over the company's handling of AI safety and part of the group that had unsuccessfully tried to oust Altman from his role.

— CNBC's Samantha Subin, Brian Evans, Kif Leswing, Leslie Josephs, Amelia Lucas, Todd Haselton and Rohan Goswami contributed to this report.

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