What’s News in Markets: Southwest Soars, AI Divergence, Costco’s Markdown

What did investors make of changes to Southwest’s famous seating strategy? And why did two big AI tech-stock names go in opposite directions? Plus, why did Costco shares get a markdown? Host Francesca Fontana discusses the biggest stock moves of the week and the news that drove them. Sign up for the WSJ's free Markets A.M. newsletter. Learn more about your ad choices. Visit megaphone.fm/adchoices