• Futures tied to the S&P 500 and Nasdaq 100 were little changed after a wave of earnings reports.
• Uber employees will soon have to catch a ride back into the office.
• General Motors is reassessing its full-year guidance amid tariff uncertainty.

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

1. Win streak

The S&P 500 notched its fifth-straight day of gains Monday — barely. The broad market index closed the session just 0.06% higher, while the Dow Jones Industrial Average rose 114.09 points, or 0.28%, and the Nasdaq Composite dropped 0.1%. All three major averages saw a volatile session, with the Dow down as much as 240 points at its low and up about 300 points at its high. Stock futures tied to the S&P 500 and Nasdaq 100 were little changed Tuesday morning after a wave of earnings reports. General Motors, UPS, Coca-Cola, PayPal, JetBlue and Pfizer all reported quarterly results before the bell, with Starbucks and Snap on deck to report after market close. Follow live market updates.

2. 'It's up to China'

China on Monday again denied that it is in talks with the U.S. to reach a trade deal, contradicting suggestions made by President Donald Trump and his aides that such negotiations are underway. In an interview with CNBC Monday, Treasury Secretary Scott Bessent said that "it's up to China to de-escalate." Meanwhile, American consumers are feeling the effects of the tariff standoff between the U.S and Beijing. Chinese e-tailer Temu has started adding "import charges" of about 145% to shoppers' totals in response to Trump's tariffs. The line item comes after Temu warned earlier this month that it planned to raise its prices "due to recent changes in global trade rules and tariffs."

3. Reaching for the Star(link)

Amazon's latest delivery? Twenty-seven satellites sent roughly 280 miles above Earth's surface. After an earlier attempt was scrubbed due to bad weather, the tech giant on Monday launched a rocket carrying the first batch of its Kuiper internet satellites into space. The launch comes six years after Amazon first unveiled Project Kuiper, its plan to build a constellation of internet-beaming satellites in low Earth orbit. With the project, Amazon hopes to take on Elon Musk's Starlink, which currently dominates the market. But it has its work cut out for it: The Federal Communications Commission expects Amazon to have half of its total constellation, or 1,618 satellites, launched by July 2026.

4. Return trip

Uber employees will soon have to catch a ride back into the office. In a memo seen by CNBC, CEO Dara Khosrowshahi told employees — including those previously approved to work remotely — that it will require them to come to the office three days a week. "As we head into this next chapter, I want to emphasize that 'good' is not going to be good enough — we need to be great," Khosrowshahi said in the memo Monday. Employees must work from the office Tuesday through Thursday starting in June, according to the memo, which also announced a change in its sabbatical policy. Employees will now be eligible for a one-month paid sabbatical after eight years at the company, up from five years.

5. Rerouting...

Shares of General Motors dropped more than 2% in early morning trading Tuesday after the automaker beat top- and bottom-line estimates for the first quarter but said it is reassessing its full-year guidance amid tariff uncertainty. GM's 2025 financial guidance released in January did not take tariffs into account. "We believe the future impacts of tariffs could be significant," CFO Paul Jacobson said during a media call. "The prior guidance can't be relied upon, and we'll come back to the market with clarity as soon as we have it." The White House said Tuesday that it will take steps to reduce the impact of Trump's auto tariffs.

— CNBC's Sean Conlon, Pia Singh, Alex Harring, Jeff Cox, Kevin Breuninger, Gabrielle Fonrouge, Annie Palmer, Jennifer Elias and Michael Wayland contributed to this report.