What happens if a whale makes a bad trade?

If a whale places a losing trade and you're auto-copying them, your position will mirror theirs — including the loss. This is the fundamental risk of copy trading: you inherit both the upside and the downside of the traders you follow.

There's no automatic stop-loss built into Polymarket prediction markets. A position either resolves as a win (you get paid) or a loss (you lose your stake), so losses are binary — you can lose your full trade amount on any single position.

To limit your exposure, use paper trading mode to evaluate whales before going live, keep your max trade size conservative, and diversify across multiple whales rather than concentrating on a single trader. These guardrails won't eliminate risk, but they'll help manage it.