SEC Form 4 filings, cluster buys, and what actually predicts stock performance.
When executives, directors, or major shareholders (10%+ owners) of a public company buy or sell their own stock, they must file a Form 4 with the SEC within 2 business days. These filings are public and free to access.
This is completely legal to use in your investment research. The illegal kind of insider trading involves acting on material non-public information (MNPI) that hasn't been disclosed. Once a Form 4 is filed, it's public data available to everyone.
Company insiders have the deepest knowledge of their business: revenue trajectory, pipeline health, competitive dynamics, and upcoming catalysts. When they spend their own money buying shares on the open market, it's a high-conviction signal about the company's future.
Academic research consistently shows that insider purchasing outperforms the market. The key is knowing which insider transactions are meaningful and which are noise.
| Transaction Type | Signal Strength | Why |
|---|---|---|
| Open-market purchase | Strong bullish | Insider chose to spend their own money at market price |
| Cluster buy (multiple insiders) | Very strong bullish | Multiple people with inside knowledge buying simultaneously |
| 10b5-1 plan sale | Weak/neutral | Pre-scheduled — not a real-time decision |
| Options exercise + immediate sell | Neutral | Often tax-driven, not conviction-driven |
| Unplanned open-market sale | Moderate bearish | Insider chose to sell — but could be diversification |
| Large purchase relative to salary | Very strong bullish | Insider betting meaningful portion of net worth |
When 3+ insiders at the same company buy within a 2-week window, it signals broad internal confidence. This is far more predictive than a single insider buying. The CEO, CFO, and two directors all buying? That's conviction across different vantage points.
A CEO buying $50,000 of stock when their salary is $15M is noise. A VP buying $200,000 when their salary is $300,000 is putting serious skin in the game. The ratio matters more than the absolute dollar amount.
CEOs, CFOs, COOs, and division heads have more operational insight than board members. Their purchases tend to be more predictive because they're closer to the day-to-day business performance.
When insiders buy after a stock has dropped 20%+, they're signaling the decline is overdone relative to their knowledge of the business. This "buying the dip" pattern from insiders has strong historical predictive power.
An insider who has never voluntarily purchased shares before suddenly buying is more noteworthy than someone who buys small amounts routinely. It suggests something changed in their assessment.
The Fin45 AI agent monitors SEC EDGAR Form 4 filings in real time across all 495 S&P 500 companies. The scoring system evaluates:
An insider signal alone won't trigger a trade — it must achieve ≥ 0.75 conviction AND have confluence with other independent data sources.
Yes, completely legal. Form 4 filings are public disclosures. What's illegal is trading on material non-public information (MNPI) — information not yet disclosed. Once filed with the SEC, anyone can use this data for investment research.
A cluster buy occurs when 3 or more company insiders purchase stock on the open market within a short window (typically 2 weeks). This signals broad internal confidence and is far more predictive than a single insider purchasing.
Under SEC rules, insiders must file Form 4 within 2 business days of a transaction. Most filings appear on EDGAR the same day or next day. Fin45 monitors these filings in real time.
Academic research shows that insider open-market purchases outperform the market by 6-10% annually on average. The signal is strongest for cluster buys, large purchases relative to compensation, and C-suite officers buying after price declines.
Fin45's AI agent monitors all SEC Form 4 filings across 495 S&P 500 companies in real time. It scores transactions based on type, cluster detection, relative size, insider role, and context. Insider signals must achieve ≥ 0.75 conviction and have confluence with other data sources (options flow, dark pool, etc.) before triggering a trade.