Group 1 - Warren Buffett is a prominent investor known for his long buy-and-hold strategies, with Berkshire Hathaway's annual meeting attracting thousands of investors [1][2] - Berkshire Hathaway's portfolio is heavily concentrated, with three companies making up over 50% of its total holdings, a strategy that has proven successful over the years [2][5] - The investment philosophy emphasizes buying good companies with globally recognized products and services while paying dividends [5] Group 2 - American Express is a multinational financial services corporation specializing in payment cards, with a strong performance in 2025 and a dividend yield of 0.92% [6] - The company reported earnings per share of $4.14, exceeding analyst expectations of $3.99, marking a 19% year-over-year increase, with revenue growing 11% to $18.43 billion [7] - American Express's net income reached $2.9 billion, up 16% compared to the previous year, and it serves a diverse customer base including consumers, small businesses, and large corporations [7][8]