How to read an insider trade (and why 90% of them are noise) 🧵:
Every week someone posts a screenshot, "INSIDER DUMPS $40M IN STOCK!", and the replies panic. Most of the time, nothing happened. The executive didn't sell a thing. Learning to tell the difference is one of the highest-value skills in markets, and it takes about ten minutes to learn.
Here's the foundation. Every officer, director, and big shareholder has to report their trades to the SEC on a Form 4, usually within two business days. It's public, free, and fast. The catch is that the filing buries the one field that matters under a pile of stuff that doesn't.
That field is the transaction code. Get it right and everything else falls into place:
P is an open-market purchase. The insider spent their own cash to buy shares in the open market. This is the signal. It's the one code that's genuinely hard to fake, because nobody writes a personal check for stock they think is going down.
S is an open-market sale. Weak signal on its own. People sell for a thousand reasons that have nothing to do with the company: taxes, a divorce, a house, diversification.A is a grant, F is shares withheld for taxes, G is a gift, M is an option exercise. These four are where the fake "insider selling" headlines come from. When an exec's RSUs vest, the company automatically holds back a chunk of shares to cover the tax bill. That shows up as code F, and a careless headline calls it a "sale." It isn't. The exec didn't decide anything. Same with gifts (estate planning) and grants (just compensation landing).
So that "$40M dump"? Pull the filing. Nine times out of ten it's a wall of F and G codes, vesting mechanics and a trust transfer, not a single dollar of conviction.
Now the second filter, and this is the one even semi-pros miss: was the trade pre-scheduled? There's a thing called a 10b5-1 plan, a program an insider sets up months in advance to buy or sell automatically, specifically so they can't be accused of trading on inside information. A sale under a 10b5-1 plan was decided long ago and tells you nothing about today. A purchase made outside any plan, the insider choosing, right now, to buy, is the version with information in it. The filing flags which is which. Always check.
Then there's the part that separates a casual reader from someone with an edge: a single buy can be random, but a cluster isn't. When two co-CEOs and a CFO all buy on the same day, with their own money, no plan, that's not three coincidences. That's a shared view forming inside the company at the moment it matters. Clusters are the highest-conviction insider signal there is, and they're invisible if you're only looking at one filing at a time.
One more layer, because not all P-codes are equal either. An insider "buying" by converting debt they were already owed into equity will still show up as a purchase, but it's a restructuring, not a bet. A founder writing a fresh personal check is a different animal entirely. The footnotes tell you which one you're looking at. Read them.
Put it together and you have a filter most of the market doesn't use: ignore the S, A, F, G, M noise, weight the discretionary, non-plan P buys, prize the clusters, read the footnotes for what kind of buy it really is. Do that and "insider selling" headlines stop scaring you, and the rare, real conviction buys start standing out.
The honest problem is scale. Doing this by hand means reading thousands of filings a week, decoding codes and plan flags and footnotes on every one. No human keeps up. That's the entire reason SecBot exists. It reads every Form 4 across 8,000 tickers, filters the noise, scores the clusters, and surfaces the handful that actually mean something. But even if you never touch the tool: now you can read the filing yourself. That's the part nobody teaches.