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Value Investing Library

Timeless wisdom from the greatest investors, free forever.

Warren Buffett Complete Library

Search and download interviews, speeches, books, and shareholder letters

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Featured Articles(23)

100 Buffett Principles25 min

The 10 Commandments of Value Investing

The ten value investing principles of Buffett and Munger — margin of safety, circle of competence and intrinsic value — explained with Berkshire examples.

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50 Charlie Munger Lessons35 min

Mental Models: The Latticework Theory

Why Munger argued you need mental models from multiple disciplines to make good decisions — and how the latticework changes an investment checklist.

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Annual Letters Archive45 min

2024 Berkshire Shareholder Letter Highlights

Key takeaways from Buffett's 2024 Berkshire shareholder letter: record operating earnings, insurance float, the Treasury-bill pile and 59 years of compounding.

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Investment Psychology30 min

Why Investors Sell at the Worst Time

The emotional traps that cause investors to buy high and sell low — and the pre-commitments that stop investment psychology from costing you returns.

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Economic Moat30 min

How to Identify a Wide Moat Business

A practical framework for evaluating competitive advantages that last: pricing power, switching costs and the tests that separate a wide moat from a story.

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Capital Allocation30 min

The Art of Capital Allocation

What separates great CEOs from good ones is capital allocation: buybacks, acquisitions and reinvestment, judged by return on invested capital.

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Circle of Competence14 min

Circle of Competence: The Boundary That Protects Your Returns

Why knowing what you do not know matters more than knowing more, and how to draw the boundary honestly.

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Margin of Safety13 min

Margin of Safety: The Central Concept of Investing

Graham called it the central concept of investment. Here is how to actually quantify it instead of gesturing at it.

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Book Reviews12 min

Book Review: The Essays of Warren Buffett

Lawrence Cunningham organised four decades of shareholder letters into one coherent book. Here is what it actually teaches.

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100 Buffett Principles16 min

How Buffett Survived Every Market Crash Since 1962

Six decades of crashes, none of them predicted. The repeatable posture that let him act instead of freeze.

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50 Charlie Munger Lessons13 min

Inversion: The Mental Model That Solves Problems Backwards

Why asking how you would lose money is more productive than asking how you would make it.

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Investment Psychology12 min

Loss Aversion: Why You Sell Winners and Keep Losers

The disposition effect quietly fills portfolios with failures. Two questions break the pattern.

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Economic Moat13 min

Moat Erosion: How Great Businesses Lose Their Edge

Moats do not vanish overnight. Four early warnings that a competitive advantage is quietly draining.

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Capital Allocation12 min

Buybacks: When They Create Value, and When They Destroy It

A buyback is not inherently good or bad. The only question is what the company gave up to buy its own shares.

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Circle of Competence11 min

The Cost of Leaving Your Circle of Competence

You do not need to know everything. You need to know the boundary, and what happens when you cross it.

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Annual Letters Archive12 min

Mistakes of the First Twenty-Five Years

Buffett devoted a whole section of his 1989 letter to his own errors. It remains the best writing he has done.

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Margin of Safety13 min

Estimating Intrinsic Value Without Fooling Yourself

A practical valuation routine built around one goal: preventing your own assumptions from being hidden from you.

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Book Reviews12 min

Book Review: The Intelligent Investor

Graham's 1949 book defined the discipline. Three of its ideas still do the heavy lifting.

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Valuation Methods14 min

Discounted Cash Flow Explained: The Formula, Step by Step

Every input of a DCF, what each one assumes, and the two places virtually every model quietly breaks.

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Valuation Methods13 min

Return on Invested Capital: Good Business vs Bad Business

The ratio that connects business quality to compounding, and the four ways it gets quietly distorted.

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Investment Psychology13 min

When to Sell a Stock: The Value Investor Exit Checklist

The four reasons that justify selling, the three that do not, and the one question that removes your cost basis from the decision.

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Margin of Safety12 min

How Concentrated Should Your Portfolio Be? Position Sizing

Concentration is not about a number. It is about what you know, what you correlate with, and what drawdown you can actually hold through.

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Money & Behavior6 min

The 5x Gap Nobody Talks About

Identical salaries, identical returns, twenty-five years. One household ends with five times more — and the variable that caused it was never stock picking.

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“An investment in knowledge pays the best interest.”

- Benjamin Franklin (quoted by Buffett)