🔄 Multiple Insiders Buying at the Same Time
Cluster buying is triggered when two or more distinct insiders at the same company purchase shares within a 14-day window. Unlike a single insider acting alone, coordinated buying from multiple executives or directors sends a much stronger signal of collective confidence in the company's prospects.
Live insider transactions with this signal active across 13 European markets.
How it works
Academic research consistently identifies cluster buys as one of the most reliable insider trading signals. Jeng, Metrick & Zeckhauser (2003) found that portfolios tracking cluster insider purchases generated significant abnormal returns over 6-month horizons. The underlying logic is straightforward: when multiple insiders independently decide to buy at similar price levels and in a short time window, it suggests they share a common, undisclosed conviction about the company's value — without necessarily coordinating or communicating about it.
Detection methodology
InsidersAlpha fires the cluster signal when two or more distinct named insiders (CEOs, CFOs, board members, or closely associated persons) at the same company submit buy filings with transaction dates within 14 calendar days of each other. Corporate entity transactions without identified individual names do not count toward the cluster threshold.
Frequently asked questions
What counts as a cluster buy?
InsidersAlpha requires at least two distinct named insiders at the same company to have purchase transaction dates within a 14-day window. The insiders must be separate individuals — a single person buying twice does not trigger a cluster signal (that triggers the Repetitive Buying signal instead).
How reliable is the cluster buying signal?
Jeng, Metrick & Zeckhauser (2003) found insider purchase portfolios generated 11.2% abnormal returns in the six months following the transaction. Cluster purchases, where multiple insiders buy together, are associated with even stronger returns. However, no signal is infallible — cluster buys can occur before corporate restructurings, management buyouts, or other events that may not benefit minority shareholders.
How common is cluster buying?
InsidersAlpha currently detects cluster buying signals at roughly 80–120 companies per month across its 13 covered markets. Cluster buys are more common during broad market drawdowns when valuations compress and executives buy on weakness.
Does InsidersAlpha show historical cluster buy data?
Yes. Pro and Elite subscribers can view the full 180-day history of cluster buy signals with post-trade performance tracking at 30, 90, and 180 days.
Other insider signals
InsidersAlpha tracks five distinct insider trading signals. They can fire independently or in combination — co-occurrence of multiple signals on the same transaction is associated with higher conviction.
See our methodology page for a full explanation of how all signals are calculated.