October 2025’s Stock Market Highlights: AMD Soars 62% on OpenAI Deal, Fiserv Struggles
Advanced Micro Devices (AMD) led October's market rally with a 62% surge—its strongest monthly performance since 2001—after securing a pivotal AI chip supply agreement with OpenAI. The deal underscores the accelerating convergence of semiconductor and artificial intelligence technologies.
Memory chipmaker Micron Technology (MU) and automation tester Teradyne (TER) followed with gains of 36% and 33% respectively, while J.B. Hunt Transport Services (JBHT) rebounded 25% on cost control measures. Western Digital (WDC) rounded out the top performers with a 23% climb, fueled by cloud and AI-driven demand for data storage solutions.
Payment processor Fiserv (FI) anchored the month's declines, though specific performance metrics were truncated in the source material. The contrast between tech-sector momentum and financial services' struggles highlights the market's continued rotation toward AI-exposed assets.
