The edge, explained
Why insider buying works, how we read the SEC's Form 4 feed, and what we filter out.
Why following insiders works
Everyone online has an opinion. Insiders bet their own after-tax money.
The research
Anyone with real market experience pays close attention to what insiders are doing. After all, who knows a business better than the people running it? The definitive academic study (Seyhun, MIT Press) backs it up: firms with net insider buying beat the market. Net sellers lagged it.
The logic
The natural state of management is to be a seller. Most companies pay heavily in stock and options, so sales alone tell you little. Insiders sell for a hundred reasons: taxes, a house, a divorce. They buy for one: they think it's going up.
The Form 4 filing
Whenever a corporate insider, such as an officer, director, or beneficial owner of more than 10% of a company’s stock, trades company securities, it must be submitted electronically via the SEC EDGAR system within two business days of the transaction. Most people don't keep track of it 24/7. We do.
How to read a Form 4
The SEC's raw feed is thousands of filings a week, most of it is insignificant. Harvey screens the tape by hand so what you see is always relevant. Here's the column he reads first, straight off the form:
Six codes on the form. Five get filtered out by hand. Everything on our tape starts at P because an insider writing a personal check is the only line on a Form 4 that can't be explained away.
What makes a buy worth watching
"P" codes only: open-market buys, not grants.
CEOs, CFOs & directors over junior officers.
Buys at or above market price, not waiting for a dip.
Multiple insiders and the same name means a louder signal.
No single marker is a green light on its own. The more that stack up, the more the buy earns a closer look.
What we ignore, and where we're honest
We have lost money following insiders, and we curse aloud: what were they thinking! That's exactly why every buy still has to earn its way through the filter above. Harvey · The Insomniac Hedge Fund Guy
What we read every day
The raw data is free from the SEC. The edge is in how you organize it and in reading what everyone else skips.
Every Form 4 hits the SEC's EDGAR system within two business days. Free, public and almost nobody reads it 24/7.
Our subscription for managing the vast realms of filing data. A smaller vendor whose founder trades on his own data. We like people who eat what they kill.
Our go-to financial news service for showing us what's moving around a filing: earnings, analyst comments, and whatever else could be pushing the stock while the insider was buying.
Wire services are for speed. For what a business actually does, we probe the 10-K: the most accurate, succinct description a company will ever give you.
Notable winners
Real insider buys we tracked, bought at the Form 4 price, marked to today’s close. This is what following conviction looks like.
| Ticker | Buy price | Return | Annualized | |
|---|---|---|---|---|
| 1 | AAOIApplied Optoelectronics · Fiber-optic components for data centers and broadband networks | $22.54 | +438% | +594% |
| 2 | TTMITTM Technologies · Printed circuit boards for aerospace, defense & computing | $41.32 | +278% | +373% |
| 3 | MRVLMarvell Technology · Data-infrastructure and AI semiconductor company | $77.09 | +219% | +367% |
| 4 | MUMicron Technology · Memory and storage chips (DRAM & NAND) | $337.14 | +190% | +982% |
| 5 | INTCIntel · Semiconductor maker — processors and chip foundry services | $42.50 | +183% | +1,138% |
| 6 | CNCCentene · Managed-care health insurer for government programs | $25.50 | +166% | +205% |
Marked to verified prices as of July 5, 2026. Annualized extrapolates each holding period and is not a forecast. Past performance is not indicative of future results.
The tape shows you who's buying. The Guy's Active Picks show you where we're putting our conviction.
