Polymarket volume inflated by ‘artificial’ activity, study finds

A new Columbia University study alleges that Polymarket, a prominent prediction market, has experienced significant "wash trading," artificially inflating its reported activity by an average of 25% over the past three years, with peaks as high as 60% last December. This practice, where users engage in risk-free, self-matched trades, undermines the platform's perceived market strength and the reliability of its volume as a true reflection of crowd sentiment, particularly given its crypto-based, fee-free structure and potential token incentives. The findings raise critical questions about the authenticity of activity metrics in crypto-based exchanges and could influence investor perspectives, such as Intercontinental Exchange's recent $2 billion investment in Polymarket.

Analysis

A new Columbia University study reveals that Polymarket, a prominent prediction market, has experienced significant wash trading, artificially inflating its reported activity by an average of 25% over the past three years. This "artificial trading" peaked at 60% last December and stood at approximately 20% in early October, undermining the platform's perceived market strength and the reliability of its volume as a true reflection of crowd sentiment. The study highlights that such fictitious volume does not add liquidity or information, potentially distorting market efficiency.

The prevalence of wash trading is attributed to Polymarket's crypto-based structure, including its fee-free transactions and the ability to create multiple pseudonymous wallets on the Polygon blockchain. Researchers suggest users may be incentivized by the prospect of gaining access to a proprietary digital token through "airdrops" rewarding frequent users. This practice is generally viewed by US regulators as market manipulation, adding a layer of scrutiny given Polymarket's past $1.4 million CFTC settlement and plans for a US return.

These findings emerge amidst a competitive landscape where Polymarket's chief rival, Kalshi, has recently attracted more trading. The study's implications are particularly relevant for investors, including Intercontinental Exchange Inc. (ICE), which recently announced an investment of up to $2 billion in Polymarket. While the study's authors note their estimates are not definitive, the potential for large-scale wash trading raises concerns about the authenticity of platform activity metrics, especially in cryptocurrency-based exchanges.

Key Decisions for Investors

• Investors should critically re-evaluate Polymarket's reported trading volumes, recognizing that a significant portion may be artificial and not indicative of genuine market interest or liquidity.
• Closely monitor Polymarket's response to the study, any proposed changes to its platform structure, and ongoing regulatory developments, particularly concerning its planned US re-entry and CFTC compliance.
• Re-assess the competitive positioning against rivals like Kalshi and the long-term investment thesis for prediction market platforms, especially considering the impact of potentially manipulated metrics on valuation and growth projections for entities like ICE.