5 things to know before the stock market opens Friday, September 15

Here are the most important news items that investors need to start their trading day:

The Dow Jones Industrial Average saw its best day in more than a month on Thursday. Traders were cheering a successful major IPO and a decent batch of economic data. The Dow rose 331.58 points, or 0.96%, and closed above its 50-day moving average for the first time since Sept. 1. The S&P 500 rose about 0.84% while the Nasdaq Composite was 0.81% higher. In economic news, the headline producer price index rose 0.7% in August, stronger than economists’ expectations of 0.4%. However, the core PPI increased by 0.2%, in line with estimates. Stock futures were ticking higher Friday morning. Follow live market updates.

Thousands of United Auto Workers members are on strike at three key auto plants after the union and the Detroit automakers failed to reach a deal by a Thursday night deadline. UAW President Shawn Fain is taking a new approach by negotiating with all three companies at the same time. In the past, the UAW would typically focus on contract talks with one automaker. The facilities where workers are striking are GM’s midsize truck and full-size van plant in Wentzville, Missouri; Ford’s Ranger midsize pickup and Bronco SUV plant in Wayne, Michigan; and Stellantis’ Jeep plant in Toledo, Ohio. About 12,700 workers will be on strike, the union said. It represents about 146,000 across the three automakers.

Arm Holdings is officially trading on the Nasdaq. It rose nearly 25% during its first day of trading on Thursday after its initial public offering priced at $51 per share. Arm was valued at nearly $60 billion when it opened. It sold around 95.5 million shares, but SoftBank still owns about 90% of the British chip design company. After the debut, Arm is now priced at a premium to Nvidia despite Nvidia’s revenue doubling in the most recent quarter with rosy revenue projections while Arm’s revenue shrank in the latest period. Arm’s architecture is used in nearly every smartphone chip and it makes a significant amount of money from royalties.

Another airline is warning that high fuel prices will eat into its profits. Delta Air Lines on Thursday cut its adjusted earnings forecast for the third quarter to between $1.85 and $2.05 a share, down from an earlier forecast of $2.20 to $2.50, citing higher-than-expected fuel and maintenance costs. Earlier this week, American Airlines, Spirit Airlines and Frontier Airlines also warned that the summer quarter would be tough as higher costs would cut into their profits. Their outlook revisions followed similar moves from Southwest Airlines and Alaska Airlines. Also this week, Delta changed how customers can earn elite frequent flyer status and made it harder to get into its airport lounges, the latest reality check for air travel’s era of mass luxury.

JPMorgan Chase plans to offer digital payroll processing to small businesses, ramping up its competition with fintech players like Square and PayPal, which already have such services. The fintech players have turned their approach to become do-everything providers that threaten traditional banks. The biggest U.S. bank by assets is also hoping the move makes it appeal to more small businesses. JPMorgan selected San Francisco-based fintech player Gusto to provide the underlying technology for the feature, Gusto’s CEO said.

— CNBC’s Samantha Subin, Sarah Min Michael Wayland, Kif Leswing, Rohan Goswami, Ari Levy, Leslie Josephs and Hugh Son contributed to this report.

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