S&P 500 Adds Dicey Stocks as Market Turns Increasingly Exuberant

Over the past few years, few stocks in the US have been hotter than AppLovin Corp.

The mobile advertising technology company’s shares have soared more than 5,500% since the end of 2022, making them the second best performer in the massive Russell 3000 Index, after Carvana Co. Its market capitalization is now more than $200 billion, up from $29 billion when it went public in April 2021. Not surprisingly, it was added to the S&P 500 Index last month.

By the numbers, AppLovin seems like a typical tech high flyer. But questions have been swirling around the company for ...