What is a SEC Form 4?

US securities law defines three groups of "insiders": corporate officers (CEO, CFO, COO, Presidents, Vice Presidents), members of the board of directors, and anyone who beneficially owns 10% or more of the company’s shares. All three groups must report every transaction in their company’s stock.

The related forms matter too: a Form 3 is filed once when someone first becomes an insider (listing what they already own), and a Form 5 is an annual catch-up for small or exempt transactions. Form 4 is the timely one - it tells you what insiders are doing right now.

Each filing includes the insider’s name and role, the transaction date, a one-letter transaction code, the number of shares, the price, and the insider’s total holdings after the transaction.

The transaction codes separate signal from noise: P means an open-market purchase with the insider’s own money, S an open-market sale. Codes like A (grant), M (option exercise), F (tax withholding), and G (gift) are mostly routine compensation mechanics.

Insiders sell for many neutral reasons - taxes, diversification, buying a house. There is essentially one reason to spend personal money buying: they expect the stock to be worth more. Academic research on insider filings consistently finds that open-market purchases, especially by senior executives, carry the most information.

Greedy Insider reads every Form 4 as it lands on SEC EDGAR and scores its structural conviction from 0 to 100, so you can prioritize which filings to read first. The score describes the filing; it does not predict returns and is not investment advice.