Polymarket Whale Detection: How to Spot Insider Trading Before the News Breaks

By RangeScout Research · 8 min read · 2026-03-18

Polymarket prices often move 24-72 hours before headlines. Learn the five statistical patterns that indicate informed flow — volume spikes, thin-book whale footprints, stale-then-break moves — and how RangeScout flags them automatically.

Why prediction markets leak information

Polymarket is the purest information market on the internet. Unlike equities or crypto, there's no regulatory moat preventing someone with inside knowledge from taking a position — and the market prices it instantly. When a geopolitical event is about to happen, the people who know move size into the relevant Polymarket market hours or days before the headline hits Bloomberg. This has happened publicly on everything from Fed rate decisions to military strikes to corporate resignations. The patt...

The five patterns that indicate informed flow

1. Volume spike vs trailing median. A market that's averaged $20k/day for two weeks suddenly does $200k. That's a 10x spike. Baseline-relative volume is a better signal than absolute volume because it catches quiet markets waking up. 2. Volume / liquidity ratio > 1. If 24h volume exceeds total pool liquidity, someone is aggressively taking the book — the classic thin-book whale footprint. Institutional flow avoids this; informed retail whales cause it.

Where to start

The [Trading Signals page](/signals) shows live flagged markets in real-time. Free users get scan access with 5 credits per scan; paid tiers include the Opus profit analyzer.