Famed investor Warren Buffett loves Apple (NASDAQ: AAPL) stock, recently saying he'd "love to own 100% of it." But with Apple's total market cap recently surpassing $1 trillion, not even the Oracle of Omaha has that kind of money. Ever since first investing in Apple in 2016, Berkshire Hathaway (NYSE: BRK-A) (NYSE: BRK-B) has steadily increased its holdings nearly every quarter since.