

Core Viewpoint - Warren Buffett is deepening his investment in Japanese trading companies by increasing his stake in Mitsui & Co. to over 10%, marking him as a "major shareholder" [3][6]. Investment Strategy Shift - This increase in stake signifies a subtle shift in Berkshire Hathaway's investment strategy, as Buffett initially planned to keep holdings in these companies below 10% [6]. - The Japanese trading companies have agreed to "moderately" relax the holding limit, allowing Berkshire to surpass the 10% threshold and engage more deeply in their future developments [6]. Market Reaction - Following the announcement, Mitsui & Co.'s stock price rose by 2.2% before settling at a 1.75% increase, with other major trading companies also experiencing stock price increases [3][6]. Unique Business Value - Buffett's continued investment highlights the unique business value of Japanese trading companies, which have a highly diversified business structure, providing resilience during commodity price fluctuations [6]. - These companies have also focused more on shareholder returns, enhancing their attractiveness as investment opportunities [6].