Methodology
The rules this site applies, with the numbers currently in force. Nothing here is hidden behind the score.
Which trades count
Only open-market purchases and sales reported on SEC Form 4 (transaction codes P and S) in common stock. Awards, option exercises, gifts and other transfers are left out. A purchase below $1,000 does not count towards dollar totals. The same trade reported twice (an amendment, or co-filers of one purchase) is counted once.
What is a buying cluster
A run of purchases at one company by 3 or more distinct insiders. A pause longer than 30 days between two purchases ends the run and starts a new one. A cluster stays in the active list while 3 or more distinct insiders bought in the last 180 days. A company can therefore have several runs; the list shows the latest.
What is flagged
- Offering: IPO allocations, private placements and similar subscriptions, found from footnotes, from 8-K filings, or because 3 or more insiders bought at exactly the same price on one day near the listing or outside the day's traded range.
- Routine and plan: purchases under a trading plan (Rule 10b5-1), a dividend reinvestment or compensation plan, or with a regular cadence.
Flagged purchases stay visible and are discounted in the score. The list can hide clusters that are mostly IPO or plan buying.
The score
A weighted blend of five factors, each from 0 to 100%, times the discounts for routine and offering buying, minus a penalty for insider selling in the 90 days before.
- 25% Commitment: the size of the purchases against the company and against what the buyers already held
- 20% Breadth: how many distinct insiders bought
- 20% Seniority: the rank of the buyers
- 20% Context: buying after the stock fell against the market
- 15% Timing: purchases close together
The AI adjustment is a separate, visible number: a model reads the filings and the news around the cluster, classifies the buying, and adds or subtracts points. It is never used in the track record.
Missing data
A missing input counts as neutral and the cluster is marked "partial data"; it is never replaced with an estimate. A share count filed more than 400 days ago, or dated before the company's first trading day, gives no market cap.
Timing
What was known is decided by the SEC's acceptance time of each filing, in New York time. New filings are picked up during business days and prices are end-of-day; the site warns when its data is out of date.
Does it work?
See the track record: what followed past clusters, printed as measured.