Berkshire Hathaway Chairman Warren Buffett has consistently emphasized disciplined investing focused on acquiring high-quality, large businesses with strong management and growth potential, as outlined in his shareholder letters from 1983, 1984, and 2013. Buffett has highlighted the importance of attracting high-quality shareholders and building earning power over time. Notably, he invested $488 million in PetroChina solely based on the company's annual report, without site visits or management calls. Buffett and Vice Chairman Charlie Munger have established clear investing principles, including patience and decisiveness, with Munger reportedly deriving only one investment idea from over 40 years of reading Barron’s. Meanwhile, activist hedge fund manager Sir Christopher Hohn’s The Children’s Investment Fund (TCI) has achieved a 21% gain in the first half of 2025, driven by concentrated bets on companies such as GE Aerospace, Visa, and Microsoft. Hohn’s investment approach is characterized by a focus on a handful of ultra-high conviction stocks.