Jim Simons vs. Warren Buffett: Who Is the Greatest Investor?
Who is the best investor: Jim Simons or Warren Buffett? Jim Simons died in 2024, and Buffett returns at the end of 2025, aged 95.
Thus, it might be relevant to ask: Jim Simons vs. Warren Buffett: Who is the greatest investor of all time?
Two Titans of Investing
Jim Simons and Warren Buffett represent two of the most successful yet fundamentally different approaches to investing.
As of today, their legacies span decades, shaping financial markets through innovation, discipline, and extraordinary returns.
This article explores their strategies, achievements, and philosophies to answer a timeless question: Who is the better investor?
Who Is Jim Simons?
Jim Simons, born in 1938 and passed away on May 10, 2024, was a former codebreaker, mathematician, and the founder of the Medallion Fund.
Often dubbed the “Quant King,” Simons revolutionized investing by applying mathematical models and algorithms to predict market behavior.
His crowning achievement, the Medallion Fund, delivered an unprecedented 66% annual return (before fees) from 1988 to 2021.
Simons’ Quantitative Strategy
- Data-Driven Models: Use mathematical patterns and statistical analysis.
- Machine Learning & AI: Continuously refines predictive algorithms.
- Multi-Asset Trading: Trades stocks, bonds, currencies, and commodities.
- High Talent Culture: Hires physicists, mathematicians, and scientists over traditional finance professionals.
Despite its secrecy, Renaissance’s success has influenced a generation of quant funds like AQR and Two Sigma.
Who Is Warren Buffett?
Warren Buffett, born in 1930 and still active in 2025 but soon to retire, is CEO of Berkshire Hathaway and a long-time champion of value investing.
Nicknamed the “Oracle of Omaha,” Buffett focuses on long-term investments in high-quality companies trading below their intrinsic value.
Buffett’s Value Investing Principles
- Fundamental Analysis: Studies company balance sheets, cash flow, and management.
- Long-Term Focus: Holds investments for decades (e.g., Coca-Cola, Apple).
- Margin of Safety: Only buys stocks priced below their true worth.
- Simplicity and Discipline: Avoids industries he doesn’t understand.
Buffett’s relatable, accessible approach has made him a role model for individual investors worldwide.
Jim Simons vs. Warren Buffett: Investment Performance
| Metric | Jim Simons (Medallion Fund) | Warren Buffett (Berkshire Hathaway) |
|---|---|---|
| Average Annual Return | ~66% (1988–2021, before fees) | ~20% (since 1965) |
| Risk | High (uses leverage, complex models) | Lower (focus on stable companies) |
| Accessibility | Restricted (closed fund only for the insiders, highly technical) | Broad (publicly traded company) |
| Longevity | Peak years: 1988–2024 | Over 80 years of investing |
| Philosophy | Data-driven, emotionless | Business-focused, judgment-based |
Most Profitable Investments
- Jim Simons: The Medallion Fund is his masterpiece, generating over $100 billion in profits. Due to secrecy, individual trades are unknown. However, assets under management were capped at 10 billion USD, and thus, compounding was not an option.
- Warren Buffett: Famous for turning $40 billion into over $150 billion with Apple. Other wins include Coca-Cola, American Express, and See’s Candy. Buffett is rich because he was able to compound his assets.
Legacy and Impact on the Investment World
Jim Simons:
- Transformed Wall Street with quantitative investing.
- Inspired the rise of algorithmic and AI-driven trading strategies.
- Co-founded the Simons Foundation, donating billions to science and education.
Warren Buffett:
- Democratized investing through transparency and education.
- Popularized the annual shareholder letter as a financial guide.
- Co-founded the Giving Pledge, committing much of his wealth to philanthropy.
Simons vs. Buffett: Who Is the Better Investor?
The answer depends on your definition of “better”:
- For Maximum Returns: Jim Simons leads with unmatched annual returns, albeit in a closed, inaccessible fund.
- For Long-Term Stability: Warren Buffett’s 60+ year record offers consistent, replicable results.
- For Everyday Investors: Buffett’s approach is easier to understand and apply.
- For Institutional Innovation: Simons’ quant revolution changed how Wall Street operates.
Despite their differences, both investors respected each other. Simons once said, “There will always be a place for Buffett’s style.”
Buffett, in turn, acknowledged the power of quantitative systems — when used wisely.
Final Thoughts
Jim Simons and Warren Buffett are not just investors; they are institutions. One relied on code and algorithms, the other on judgment and patience. Their stories remind us there’s no single path to success in investing, but there is value in learning from both.