The fourth quarter has historically delivered the strongest returns for the S&P 500, averaging 4.3% gains since 1950—significantly outperforming other quarters. This seasonal strength, driven by holiday shopping surges, year-end earnings optimism, and returning investors, creates unique opportunities for strategic positioning. With 70% of Q4 periods ending positively since 1928 and current conditions favoring continued momentum, two AI-focused stocks—Vertiv Holdings and Arm Holdings—appear particularly well-positioned to capitalize on this year-end rally.