• The Dow Jones Industrial Average snapped its four-day win streak.
• Private sector hiring in May hit its lowest level since 2023.
• Circle priced its initial public offering at $31 per share, above the expected range.

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

1. Job jitters

The Dow Jones Industrial Average snapped its four-day win streak Wednesday, sinking 91.90 points, or 0.22%, on the back of much weaker-than-expected private sector hiring data. The S&P 500 closed the session essentially flat, gaining just 0.01%, while the Nasdaq Composite rose 0.32%. All three major indexes are still on track to end the week higher. But while a recent tech-led rally and positive earnings results have bolstered Wall Street sentiment, investors are still cautious that President Donald Trump's tariffs could mean more pain ahead. Follow live market updates.

2. Signs of a slowdown?

Private sector payrolls increased by just 37,000 in May, according to a report released Wednesday by payrolls processing firm ADP. The near standstill in private sector hiring was far below the Dow Jones analysts' forecast of 110,000 for the month and represents the lowest monthly job total from the ADP count since March 2023. In a Truth Social post following the data's release, Trump attacked Federal Reserve Chair Jerome Powell and urged him to cut interest rates. "'Too Late' Powell must now LOWER THE RATE. He is unbelievable!!!" the president wrote. The ADP report wasn't the only signal on Wednesday that the U.S. economy may be slowing down. In its periodic "Beige Book" summary of conditions, the Fed said that "economic activity has declined slightly since the previous report" amid tariff-related price hikes and policy uncertainty.

3. Frenemy

Elon Musk continued to attack the GOP spending bill Wednesday, posting on his social media platform X "KILL the BILL." The Tesla CEO — who until Friday worked in the Trump administration leading DOGE — wrote in another post that a new bill "should be drafted that doesn't massively grow the deficit and increase the debt ceiling by 5 TRILLION DOLLARS." New analysis from the Congressional Budget Office estimates that the Trump-backed budget bill would add $2.4 trillion to federal budget deficits over the next decade. "This is grotesque, what we're doing," Sen. Ron Johnson told CNBC's "Squawk Box" Wednesday morning. The Wisconsin lawmaker is one of a handful of Republican deficit hawks in the Senate who have said they will not support the bill.

4. AI arms race

Hoping to compete with the increasing number of companies building AI agents, Amazon on Wednesday said it created a new team within its consumer product-development unit focused on agentic artificial intelligence. The tech giant also announced it plans to invest $10 billion in new data centers in North Carolina in a push to expand its AI infrastructure. Meanwhile, Reddit sued Amazon-backed AI startup Anthropic on Wednesday, alleging that Anthropic is unlawfully using the social media company's data and platform. OpenAI CEO Sam Altman is a major shareholder in Reddit, which in May announced a partnership with OpenAI that allows the ChatGPT maker to train its models on Reddit content.

5. Full Circle

Circle Internet Group priced its initial public offering at $31 per share on Wednesday, above the expected range of $27 to $28. That puts the stablecoin issuer's total market value at $6.8 billion. Circle also increased the number of shares sold in the IPO, reflecting huge demand for the crypto company. Circle, its founder and some existing shareholders will raise $1.05 billion in the offering of 34 million shares, up from 32 million shares. The company originally planned to sell 24 million shares between $24 and $26 per share to raise just $624 million. Circle — the issuer of USD coin, the second largest stablecoin in the world — is set to become one of the most prominent pure-play crypto firms to list in the U.S. It will trade on the New York Stock Exchange under the ticker CRCL.

— CNBC's Sean Conlon, Sarah Min, Pia Singh, Jeff Cox, Kevin Breuninger, Erin Doherty, Annie Palmer, Ashley Capoot, Jonathan Vanian and Tanaya Macheel contributed to this report.