Quick Read Berkshire Hathaway (BRK.A) CEO Warren Buffett’s 90/10 rule, which allocates 90% to S&P 500 index funds, was designed for his wife’s specific circumstances and a very long-term horizon. Buffett himself does not follow the 90/10 rule, having been a net seller for 12 consecutive years while hoarding cash. Benjamin Graham recommended a more flexible 25% to 75% allocation between stocks and bonds, adjusting based on market conditions and individual circumstances. Some investors get rich while ...