15 S&P 500 Stocks Have More Than Doubled This Year

Since the start of 2026, fifteen S&P 500 constituents have seen their share prices more than double. Analysts note that most of these stocks are tied in some way to the artificial intelligence boom, spanning chipmakers to software developers. Other shared traits include significant upward revisions to earnings forecasts and successful cost-cutting initiatives. For retail investors, this highlights how a narrow group of market leaders continues to drive broad index performance. Experts warn that such concentrated gains raise risk for portfolios heavily weighted toward passive index funds.