Every time a company officer, director, or a shareholder owning more than 10% of the stock buys or sells shares, federal securities law requires them to disclose it — that disclosure is SEC Form 4, and it is public within days of the trade. It is one of the few places retail investors see what insiders are actually doing with their own money, not what they say in an earnings call.
Form 4 is filed by a company’s "Section 16 insiders" — officers, directors, and anyone beneficially owning more than 10% of a class of the company’s stock — every time they buy, sell, or receive shares (including option exercises and grants that vest into shares). It names the filer, their relationship to the company (officer, director, 10% owner, or some combination), the transaction date, the number of shares, the price, and the insider’s resulting total holding.
Because Form 4 is a legal disclosure requirement, not a voluntary one, the data is close to complete for the population it covers — insiders don’t get to choose which trades to report, though late filings occur and a few transaction types (certain gifts, small acquisitions) can be deferred to the annual Form 5. What it does not cover is just as important: it says nothing about the insider’s intent, nothing about trades by anyone below the 10%-owner/officer/director threshold, and nothing about hedges or derivatives positions that might offset the reported stock position.
Filers generally must report a transaction within two business days. That sounds fast, but "generally" is doing real work — late filings happen, some insiders batch multiple transactions into one filing days after the fact, and the two-day clock starts from the trade date, not from when the market (or you) can see it. By the time a Form 4 is filed, parsed, and shown on any dashboard — Quantustik’s included — the price has already moved on whatever information (or no information at all) prompted the trade.
This matters for how the data should be used: Form 4 is a record of what already happened, useful for pattern-spotting over time (is this executive a habitual buyer at lows? are multiple insiders buying in the same window?), not a real-time trade alert you can act on ahead of the market.
Insider selling is routine and usually uninformative — executives sell for diversification, taxes, home purchases, or scheduled 10b5-1 plans set up months in advance, none of which reflects a view on where the stock is headed. Insider buying is more informative on average because there are fewer routine reasons to buy, but "more informative on average" is a long way from "reliable." A single small purchase from a director with a token stake is a different signal than a CEO doubling their position, and context (cluster buying across multiple insiders, size relative to that insider’s own trading history) matters more than the raw fact of a buy.
This is why Quantustik treats Form 4 data as read-only surfacing — information to look at alongside everything else — rather than folding it into the model’s own BUY/WAIT/AVOID conviction score. An insider buy does not move a ticker’s verdict.
Every S&P 500 ticker page includes an Insider Pulse section pulling directly from SEC EDGAR Form 4 filings, with each row annotated by role (officer, director, or 10% owner), size relative to that specific insider’s own historical median trade, and whether the trade is unusually large for them. It also flags cluster buying — three or more distinct insiders buying within a 10-day window — which is a more structurally meaningful pattern than any single filing.
A companion S&P 500 screener surfaces which tickers currently have notable insider activity (a cluster buy, or a single buy well above that insider’s own norm) so you don’t have to check names one at a time. Every row links back to its source SEC filing so you can read the primary document yourself, not just a summary of it.
Form 4 has a real reporting lag (generally due within two business days of the trade, but multi-day gaps happen), and it discloses the fact of a trade, not the reasoning behind it — an insider might be buying for conviction or selling for a mortgage down payment, and the filing looks the same either way. Insider buying is not a reliable standalone predictor of outperformance: academic results on the “insider signal” are mixed and cluster mostly around small-cap, low-coverage names, not S&P 500 megacaps. Quantustik surfaces the filings and size-vs-history context; it does not fold insider activity into the BUY/WAIT/AVOID conviction score.
Educational research only — not investment advice.