In the fast-growing world of prediction markets like Polymarket and Kalshi, Introduction: The Rise of Prediction Markets and the Risks Within
Prediction markets like Polymarket and Kalshi have revolutionized the way people engage with political, financial, and social forecasting. By allowing users to trade on real-world events—such as elections, economic indicators, or celebrity outcomes—these platforms harness the “wisdom of the crowd” to price the likelihood of future scenarios.
However, as these platforms gain traction and attract both retail traders and institutional attention, they also become targets for manipulation. One of the most widespread and under-discussed tactics used by scammers is the exploitation of comment sections to spread false or misleading information.
This tactic is especially dangerous because it exploits not technology, but human psychology—particularly emotion, urgency, and herd behavior.
What Is the “Fake Comment” Scam in Prediction Markets?
The comment manipulation scam involves users (often anonymous or pseudonymous) who flood the comment sections of specific markets with fabricated or exaggerated claims. These may appear as:
- Breaking news stories that are either fake or misinterpreted
- Claims that key information has already confirmed one outcome
- False resolution criteria interpretations
- Screenshots from unrelated sources passed off as relevant proof
- Coordinated posts by multiple accounts to simulate consensus
The primary goal is to create a wave of confidence or fear, causing users—especially less experienced ones—to either rush in and buy a position or panic-sell it, depending on the narrative being pushed.
For example, in a market like “Will X politician be indicted?”, a coordinated effort of spammed comments suggesting a breaking leak could make traders rush into a Yes position—even if no such leak actually exists.
How This Scam Exploits Psychology and Market Design
Prediction markets are designed to reward accurate forecasting. But they also rely heavily on user sentiment and real-time market reactions. In this context, the comment section acts like a social signal.
Here’s why it works:
- Authority bias: If a comment is posted by a well-known wallet or trader, others are more likely to trust it without verification.
- Repetition effect: Seeing the same message over and over (especially phrased differently) creates a false sense of consensus.
- Fear of missing out (FOMO): Traders fear being late to a “sure thing,” so they jump in without proper due diligence.
- Information asymmetry: New traders may not fully understand resolution criteria or external context, making them more vulnerable.
This kind of manipulation doesn’t always require bots or advanced tools. Often, just a few highly vocal actors, spamming the same message, can sway sentiment and impact prices.
Real-World Impact: Losses and Market Distortion
The consequences of comment-based manipulation can be significant:
- Traders buy in too high or sell too low based on false signals
- Market prices become distorted, no longer reflecting real probabilities
- Confidence in prediction markets decreases, especially among new users
- Profits are unfairly extracted by those creating the misinformation
In one high-profile case on Polymarket, users spammed a market with supposed legal “proof” that a certain resolution would go one way. Despite the lack of formal verification or UMA ruling, many participants followed the narrative—only to suffer losses once the truth emerged.
How to Defend Yourself Against This Scam Tactic
Whether you’re a beginner or an experienced trader, it’s essential to develop habits that protect you from emotional, comment-based manipulation. Here are some best practices:
1. Don’t trust the comment section blindly
Treat all comments as unverified unless supported by reputable, third-party sources or official channels.
2. Understand resolution criteria
Always read the resolution criteria carefully. Many scammers prey on misinterpretations or vague wording. If you’re unsure, ask in neutral channels like Discord, not in the market’s comment thread.
3. Check user history
Before trusting a comment from a specific wallet, check its trading and comment history. Is it a known spammer? Are they pushing an agenda?
4. Cross-verify information
If someone posts “breaking news,” take 30 seconds to verify it via news outlets or fact-checking platforms.
5. Take your time
Even in fast markets, it’s better to pause and verify than to react emotionally. Scammers thrive on urgency and impulsiveness.
The Bigger Picture: A Widespread, Subtle Threat
The fake comment strategy is particularly dangerous because it’s subtle, non-technical, and hard to detect algorithmically. It’s essentially psychological warfare in a financial context.
Unlike smart contract exploits or price manipulation through volume, this scam plays on trust, emotion, and group behavior—making it one of the hardest threats to defend against at scale.
For platforms like Polymarket and Kalshi, moderation systems and community self-regulation are essential, but education remains the first and strongest line of defense.
Final Thoughts
Prediction markets are a powerful tool for forecasting the future—but they are not immune to manipulation. The comment-based scam tactic is a serious, growing issue that every trader should be aware of.
By staying calm, thinking critically, and verifying information before reacting, you can avoid becoming a victim of this subtle yet effective scam strategy.