AppLovin, Western Digital, and Warner Bros. Discovery Lead Q3 Stock Gains; Gartner Tumbles
AppLovin (APP) emerged as the S&P 500's top performer in Q3 2025, surging 104% following its September inclusion in the index. The mobile app developer's rally eclipsed even Western Digital (WDC), which gained 84% amid booming demand for data center storage solutions.
Warner Bros. Discovery (WBD) rounded out the quarter's winners with a 65% climb, fueled by acquisition speculation. Meanwhile, Gartner (IT) plunged 36% after slashing revenue forecasts, with analysts flagging existential threats from AI disruption to its consultant-driven model.