InsiderAct vs OpenInsider: Which Finds Cluster Buys Better?
OpenInsider is the most searched free insider trading tool — minimal, fast, no login required. InsiderAct is built around automatic cluster detection: flagging when 2+ corporate insiders independently buy the same stock within 30 days. Both pull from SEC EDGAR. The difference is what happens to the data after ingestion.
Quick Answer
InsiderAct auto-detects cluster buys and sends email alerts on the free tier. OpenInsider has a ‘Latest Cluster Buys’ view, but it's a date-proximity grouping with no scoring or alerts — you have to check the site manually. For passive signal tracking, InsiderAct wins. For raw data browsing and API access, OpenInsider is the choice.
Feature Comparison
| Feature | InsiderAct | OpenInsider |
|---|---|---|
| Cluster Detection | Automatic (2+ insiders / 30 days) | Manual grouping, no scoring |
| Price | Free / $19/mo Pro | Free forever |
| Email Alerts | Free tier | None |
| History (free) | 7 days | Unlimited (no paywall) |
| History (paid) | 90 days | N/A (all free) |
| Mobile UI | Responsive | Basic / desktop |
| API Access | None | Unofficial / scraping |
| Signal Scoring | Automatic | None |
OpenInsider: What It Does Well
- ✓Free, no account needed — lowest barrier to entry
- ✓Raw Form 4 data with decent filter UI
- ✓"Latest Cluster Buys" preset (date-proximity grouping)
- ✓Long track record — 10+ years of data
- ✓Developer-accessible (unofficial API / scraping)
- ✓Unlimited history with no paywall
OpenInsider: Where It Falls Short
- ✗Cluster detection is a date-proximity grouping, not a scored signal
- ✗No email alerts — have to check site manually
- ✗No watchlists — no way to follow specific tickers
- ✗No scoring: 3 directors buying $20K each looks the same as CEO + CFO buying $500K each
- ✗UI is dated, mobile experience is rough
- ✗No chart overlay — can't see whether purchase was at 52-week low
InsiderAct: What It Does Differently
- →Auto-detects clusters: 2+ insiders same stock within 30 days
- →Scores clusters — flags "Strong" or "Very Strong" based on count, dollar amount, C-suite involvement
- →Real-time EDGAR ingestion (within hours)
- →Free tier: 7-day history, 10 watchlist items, email alerts when insiders buy watchlisted stocks
- →Pro $19/month: 90-day history, 50 watchlist items, real-time alerts
- →Mobile-responsive UI
Which Should You Use?
InsiderAct wins when:
- →You want cluster signals delivered to your inbox (email alerts)
- →You want automatic scoring to distinguish strong vs weak clusters
- →You want a mobile-friendly interface
OpenInsider wins when:
- →You want unlimited history at zero cost
- →You need raw data access / developer scraping
- →You prefer no-login browsing
- →You need longer historical archives
Try InsiderAct Free
The free tier includes today's cluster buy signals, 7-day history, and watchlist with email alerts.
- ✓Today's cluster buy signals — automatically detected
- ✓7-day history of insider transactions
- ✓Watchlist with email alerts (10 stocks free)
- ✓No credit card required
Pro at $19/month: 90-day history, 50 watchlist items, real-time alerts.
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Pricing accurate as of June 2026; check each platform for current rates. Not financial advice.