ClusterSignal scans public SEC Form 4 filings every 5 minutes, detects coordinated insider activity, scores each pattern with a multi-factor algorithm, and presents results in a dense, scannable table with direct SEC EDGAR links.
A cluster is flagged when 3 or more distinct insiders file Form 4 transactions for the same ticker within any rolling 5-day window. A single insider buying is noise; three acting together is a pattern.
Transaction floors eliminate further noise. Trades under $5,000 total value are ignored entirely. VP and Director-level trades must exceed $10,000. CEO and CFO trades must exceed $25,000. The minimum aggregate cluster value before flagging is $50,000.
Each cluster receives a numerical score from 0 to 100, then a grade: A (≥80), B (≥50), or C(<50). Six factors contribute:
Insider Count
Up to 60 pts
15 pts per insider. More coordinated participants = stronger signal.
Seniority
Up to 42 pts
CEO (42) and CFO (38) carry ~3× the weight of a VP (14) or Director (10). C-suite insiders have the most complete view of the business.
Capital Deployed
Up to 22 pts
Scale-adjusted. $2M+ cluster = 22 pts. $50K cluster = 2 pts. Larger bets carry more weight.
Time Velocity
Up to 15 pts
Trades within 1 day score 13–15 pts. Trades spread over 3+ weeks score 0. Tight clustering is rare and meaningful.
Filing Speed
Up to 12 pts
Same-day filers earn maximum points. Voluntary prompt disclosure suggests insiders wanted the signal to be visible.
Win Rate
Up to 22 pts
Historical 90-day returns from prior clusters by the same insiders on the same ticker, computed when enough history exists.
Regular SOLD clusters and SHORT RADAR clusters are different. Short Radar is reserved for sell clusters that pass additional filters: $250,000+ aggregate and 3+ distinct sellers, with C-suite participation lowering the value threshold.
Routine insider sales — diversification, tax obligations, scheduled 10b5-1 plan sales — are common. A Short Radar flag indicates the sell activity is large, coordinated, and potentially out of the ordinary. It is not a short recommendation, but it warrants extra scrutiny.
Click any row on the dashboard to open the cluster's detail page. It shows: a 90-day price chart with the cluster window highlighted, the full insider trades table (with each filing's SEC EDGAR link), score breakdown, company context (market cap, P/E, next earnings), and signal flags (dilution risk, earnings proximity, volume spike, filing speed).
Pro users also see: insider track records (prior 90-day returns for each insider on this ticker), a generated signal summary, and AI-powered analysis.
Each cluster detail page includes an AI analysis section powered by Claude. On demand, it generates a 2–4 paragraph plain-English summary: what the cluster pattern means in context, what the insiders' roles suggest about conviction, and what a prudent investor might watch for — catalysts, earnings proximity, sector trends.
Every AI response ends with a mandatory disclaimer: This is not financial advice — insider buying is one data point among many. The analysis is generated fresh each time and is available to signed-in users.
ClusterSignal is a research tool, not financial advice. All data is sourced from public SEC EDGAR filings. Past cluster patterns do not guarantee future performance. Consult a licensed advisor before making investment decisions.
View live clusters, compare tiers, or read the blog for deeper context on insider cluster research.