Warren Buffett's investment in his Apple has easily exceeds his personal fortune.
Buffett owns investment conglomerate Berkshire Hathaway.
The company spent about $35 billion to buy 245 million Apple shares.
Those shares are now worth about $122 billion, representing a gain of more than $80 billion.
Buffett's net worth has sunk by $11 billion this year to $78 billion.
The decline reflects a drop in Berkshire's share price and his philanthropy.
Berkshire's Apple stake is worth more than four times as much as its Bank of America position, the second-largest holding in its portfolio.