What is a 10-K filing?

A 10-K is the annual report that every company listed on a US exchange must file with the Securities and Exchange Commission (SEC) within 60 to 90 days of its fiscal year end (depending on company size). It is the most comprehensive public document a company produces and is the starting point for any serious fundamental analysis.

The 10-K follows a standardised structure mandated by the SEC. Key sections include: Business (a description of the company's operations, products, and competitive position), Risk Factors (a frank list of material risks — this section has grown increasingly detailed over the years and is read carefully by analysts), Selected Financial Data, MD&A (Management's Discussion and Analysis) (management's own explanation of results, segment performance, and liquidity), Financial Statements (audited income statement, balance sheet, cash flow statement, and detailed notes), and Exhibits (major contracts, the CEO/CFO certifications required under Sarbanes-Oxley, and other material documents).

The 10-Q is the quarterly equivalent — a shorter, unaudited update filed within 40 to 45 days of the end of each of the first three fiscal quarters (the fourth quarter is covered by the annual 10-K). The 8-K is a current report filed within four business days whenever a material event occurs outside the normal reporting calendar — earnings announcements, major acquisitions, executive departures, bankruptcy filings, and similar events.

All 10-Ks, 10-Qs, and 8-Ks are freely available through the SEC's EDGAR (Electronic Data Gathering, Analysis, and Retrieval) system at edgar.sec.gov. Investors who want to form their own view on a company's prospects rather than relying solely on analyst summaries should start with the most recent 10-K and the subsequent 10-Qs.