S&P 500 to Add Marvell (MRVL), Flex (FLEX); Drop Pool Corp, Campbell’s

S&P Dow Jones Indices said on June 6, 2026, it will add Marvell Technology (MRVL) and Flex (FLEX) to the S&P 500 index, replacing Pool Corp (POOL) and Campbell’s (CPB) in a quarterly rebalancing. The changes take effect after the market close on June 19, 2026. Marvell, a major semiconductor designer, and Flex, a global electronics manufacturer, gain entry as their market capitalizations have grown. Pool Corp, the swimming-pool supplies distributor, and Campbell’s, the packaged-foods maker, will move to the S&P MidCap 400 index, which more closely aligns with their current market valuations. The reshuffle reflects the index committee’s periodic adjustment to ensure the benchmark accurately captures the largest U.S. stocks. Shares of Marvell and Flex traded higher in after-hours trading following the announcement, while Pool and Campbell’s slipped.