The world's approximately 100 tech billionaires collectively added a record $845 billion to their wealth through September 2026, reaching a combined $4.6 trillion. This surge was primarily driven by the AI boom and the strong performance of U.S. technology stocks. In contrast, billionaires outside the tech sector saw their wealth decrease by $62 billion. Elon Musk alone accounted for $310 billion of this increase, representing roughly 40% of the overall rise in the Bloomberg Billionaires Index.