Insider data sits at the crossing of fact and imagination. The facts are plain documents: names, dates, share counts, and prices filed under Section 16. The imagination adds secret knowledge, perfect timing, and coordinated signals that the documents rarely contain. Testing each myth against what Form 4 actually shows is a good way to reset expectations and use the data more honestly.
Insiders know a great deal about their own operations, but that knowledge has limits the myth ignores. They do not know future market conditions, competitor moves, interest rates, or how investors will react to news. They also cannot legally trade on material nonpublic information, and the trades you see on Form 4 are the lawful, reported ones, made during permitted windows and often under compliance review. Executives are frequently surprised by their own results a few quarters out, because forecasting is hard inside a company too. A purchase shows confidence and a judgment about value. It does not show foreknowledge, and treating it as foreknowledge leads readers to expect an accuracy no dataset delivers.
Selling is routine, and most of it is not a forecast. Shares are withheld or sold for taxes when awards vest. Options near expiration get exercised and sold. Long serving executives diversify after years of holding one stock for most of their wealth, pay for houses and family needs, or sell on a schedule set by a 10b5-1 plan adopted long before. Filings during any month show far more selling than buying at most companies, in good years and bad, simply because compensation constantly creates new shares for insiders to sell. The sales that deserve attention are narrower: large open market sales, by several insiders, of a big share of their holdings, with no plan or routine explanation in the footnotes. The myth collapses all sales into that small category, and in doing so makes the genuinely notable sales harder to spot.
Boards grant stock and options to pay people, and those awards appear on Form 4 with transaction code A. They are not purchases. No personal money moved, no market price was chosen by the recipient, and the award would have arrived on the same schedule if the stock had doubled or halved. This myth survives because summary tables sometimes label any increase in shares as a buy. Checking the transaction code takes seconds and removes a large share of the false signals in insider data. The same care applies to option exercises, code M, which convert an existing award into shares and say little by themselves about new confidence.
Insiders are often early, sometimes by many months, and sometimes they are simply wrong. Companies with genuine insider buying have gone on to decline, restructure, and occasionally fail, because a purchase cannot repair a balance sheet or create demand for a product. The myth also ignores price. An insider who bought at a price the market has since run far above may have been right, while a follower buying the same filing weeks later at a much higher price is making a different and worse bet. A filing is a dated fact about a past trade at a stated price, not a standing promise about the future at any price.
Silence is weak evidence. Insiders may not buy because trading windows are closed for much of the year, because they already hold large positions, because company policy or personal finances discourage it, or because they are waiting for a plan or financing to settle. Many successful companies show little open market buying for years while their executives hold substantial stakes acquired through pay. Absence of buying becomes meaningful only in context, for example when a stock has fallen sharply, management publicly calls it undervalued, windows are open, and still nobody buys. Even then it is a question to research, not a conclusion.
Strip away the myths and what remains is still useful: a timely, public, verifiable record of how a defined group of informed people used their own money. That record rewards careful reading and punishes magical thinking.
To close plainly: this article is educational commentary on public filings, not investment advice.