JPMorgan Chase CEO Jamie Dimon credits his early investment training to a rigorous childhood game he played with his father, a stockbroker, much like the legendary investor Warren Buffett's formative years.

In a recent episode of the "Top Investor Podcast," Dimon recalled that his father would challenge him to analyze a specific industry, such as restaurants. "He would say, 'Go ahead, study it. Look at its history, read the annual reports, and if you want, dive deep into the entire sector. What price would you pay to buy a share of this company's stock?'" Dimon explained. This early training built the foundation for his financial acumen.

Now 70 years old, Dimon has led JPMorgan for nearly 20 years, transforming it into the largest bank in the United States. However, the instinct to evaluate a company's fair value was cultivated long before business school, through sessions with his father, Theodore Dimon, a Wall Street stockbroker.

Theodore encouraged his three sons to learn about financial markets, but only Jamie fully embraced the challenge. While his brothers showed little interest, Dimon excelled at analyzing large-scale business investments, using the simulation game to master stock selection logic and the underlying decision-making process. "The exercise was incredibly difficult and had a high barrier to entry," Dimon admitted. "But once you mastered it, you could understand the fundamental logic behind it."

During high school, Dimon's reading habits differed sharply from his peers. He spent his free time studying psychology, economics, accounting books, academic papers, and financial reports. "I read Graham and Dodd's works in high school, and I was a nerd. I also read all of Freud's works, constantly absorbing knowledge from various fields," he said.

In 1970, at the age of 14, Dimon made his first stock investment under his father's guidance, marking the beginning of his deep involvement in the investment world. He graduated from Tufts University and later earned an MBA from Harvard Business School. After school, he entered Wall Street as an assistant to Sanford "Sandy" Weill, then president of American Express.

In a 1984 interview with Fortune, the 28-year-old Dimon shared his philosophy: "My primary goal is to build knowledge. I don't talk much until I can create value." His time working under Weill became a real-world business school. Dimon joined American Express in 1982 as an assistant to Weill, and in 1986, they left together to take over the consumer credit company Commercial Credit Corporation, where the 30-year-old Dimon served as CFO.

Under Weill's guidance, Dimon learned the entire operational logic of the banking industry, which later helped him secure top executive roles at Citigroup and Bank One. In 2004, Bank One merged with JPMorgan Chase, and in 2006, Dimon officially became CEO of JPMorgan Chase.

Today, Dimon is one of the few Wall Street bank CEOs who remained in his position through the 2008 financial crisis. According to ESGauge data, his nearly 20-year tenure at JPMorgan Chase is notably longer than the average CEO tenure of less than a decade among his peers. JPMorgan has now firmly established itself as the top bank in the U.S., ranking 12th on the Fortune 500 and 19th on the Global 500. According to JPMorgan's 2025 annual report, the bank's annual revenue reached $185.6 billion, an increase of $5 billion from the previous year.

Dimon's financial success has also generated substantial personal wealth. The Bloomberg Billionaires Index estimates his net worth at $3.2 billion.

Dimon's management philosophy When asked if he always believed JPMorgan would approach a market capitalization of $1 trillion, Dimon's response was straightforward: "I never thought about it." He stated that his management logic is based on discipline, not blind ambition. While his financial interest was sparked by his father's early influence, his management approach draws inspiration not only from Wall Street peers but also from top professional athletes.

Citing NFL legends Tom Brady and Peyton Manning as examples, Dimon said, "If you focus only on becoming the largest bank in the world, you can easily go astray. Both of these star players admitted that they didn't have the strongest arms or the best running ability, but they still became the best in their field." This is not the first time he has shared this concept. During the 2025 Fortune Most Powerful Women Summit, Dimon told Fortune editor-in-chief Alyson Shontell that he is dedicated to "giving 100% effort every single day and in every meeting."

Hard work does not always lead to success, but diligence is essential. "No one hits a home run every time they step up to bat," Dimon told Shontell. "The key is to keep working hard, stay humble, and be diligent."

The lesson his father taught him over annual reports half a century ago remains unchanged: do solid research and understand the underlying logic.