Fundamentals: Reading a business from its own filings

Fundamental analysis starts from one premise: a share of stock is a claim on the cash a business produces over its lifetime. These lessons teach you to assess that claim from the company’s own filings rather than from a headline or a price chart. You work through the three statements every public company files — the income statement, the balance sheet, and the cash flow statement — and learn why they can tell three different stories about the same quarter, and which one to believe when they disagree.

From there the library moves into the quality of what those statements report. Revenue that arrives as a multi-year contract is worth more than revenue booked on a one-time hardware sale. Gross margin tells you about pricing power, operating margin about cost discipline, and the gap between accrual earnings and free cash flow tells you whether reported profit is actually being collected. You will spend real time on working capital — inventory, receivables, payables — because that is where cash quietly leaks out of otherwise healthy income statements, and on return on invested capital, the number that separates a business that compounds from one that merely gets bigger. Alongside the arithmetic sits the qualitative half: switching costs, network effects, scale economics, brand, and regulatory position, and how to judge whether a moat is widening or being competed away.

Valuation gets its own long run of articles. Price-to-earnings, EV/EBITDA, price-to-book, and free-cash-flow yield each answer a different question and each fails in a specific way — P/E on cyclicals at the top of a cycle, book value on asset-light software, EBITDA on capital-intensive businesses that must keep spending to stand still. You will build a discounted cash flow model, then learn how sensitive it is to the two inputs almost nobody defends properly: the discount rate and the terminal value. Share count is treated as a first-class variable, since stock-based compensation and buybacks can move per-share results more than the operating business does. Dividends, payout ratios, and coverage close out the shareholder-return material.

A final group of lessons covers reading filings defensively: revenue recognition changes, one-time charges that recur every year, costs moved onto the balance sheet, receivables growing faster than sales, and the footnotes where the interesting disclosures usually live. Start with the beginner articles if you have never opened a 10-K; the intermediate and advanced sets assume you can already find your way around one.