Trump’s tariffs, including new levies that took effect Thursday, are affecting global markets. Follow along for live updates on the Dow, S&P 500 and Nasdaq.

Shares of Fortinet were off 25.7% in afternoon trading Thursday. That could mark their worst one-day slide on record if losses of such magnitude hold through the close. Opinion: AI bots aren't just ...

In a note on Wednesday following the company's monthly sales results, the UBS analysts, led by Michael Lasser, said a slowdown in May and June led some investors to conclude that Costco was running ...