TMTPOST — SoftBank Group Corp. surpassed Toyota Motor Corp. on Monday to become Japan's most valuable company by market capitalization, marking the first time in over two decades that the automotive giant has relinquished the top spot. Driven by surging global investor enthusiasm for generative artificial intelligence infrastructure, SoftBank's stock rallied over 8% to hit an all-time high. The surge pushed the technology investment firm's total market valuation above 46 trillion yen (approx. 288 billion USD), fueled by its pledge to invest up to 75 billion euros to build an AI computing cluster network in France. Meanwhile, Toyota's shares slid nearly 4.5%, dragging its total valuation below the 46 trillion yen threshold. Market analysts view the structural shift as a major milestone reflecting a broader re-rating of Japanese equities, where AI-driven growth expectations are increasingly eclipsing traditional manufacturing sectors.SoftBank has effectively positioned itself as the primary vehicle for regional tech investments through its substantial exposure to ChatGPT developer OpenAI and its controlling stake in Arm Holdings. Toyota had consistently maintained its position as the nation's market value leader since December 2003, when it originally overtook telecommunications giant NTT Docomo.