Is Polymarket Legit? What the Data and the Regulatory Record Actually Show (2026)

TL;DR

• Polymarket is a legitimate exchange. It has no record of withholding user payouts, it settles onchain in dollar stablecoins, and it has been backed by roughly $2 billion from Intercontinental Exchange (owner of the NYSE) since October 2025.
• Its US history is real. The CFTC fined it $1.4 million in January 2022 and made it block US users. A federal investigation that included an FBI search of the CEO's home ended in July 2025 with no charges. Polymarket then bought the CFTC-licensed exchange QCX for $112 million and launched a regulated US app in late 2025.
• The integrity record is mixed. A Columbia University study estimated about 25% of historical Polymarket volume was wash trading, peaking in late 2024. Several markets have had high-profile resolution disputes. Users lost funds in phishing attacks and in a June 2026 front-end attack, and Polymarket pledged full refunds for that attack.
• As of September 2026, Polymarket is fighting state regulators (Nevada, New York, Massachusetts) and faces a reported CFTC investigation after a Wall Street Journal report on its compliance practices. None of these proceedings has found fraud against traders.

That's the short version. The rest of this review goes through each part of the record in plain terms: how the platform works, the regulatory history, the payout mechanics, the wash trading research, resolution disputes, security, insider trading, the latest headlines, and how Polymarket compares with the other four platforms PredictionHero tracks.

Searching "is Polymarket legit" because a friend sent you a market, or because you just saw a headline about lawsuits and hacks? The honest answer comes in two parts.

Is it a real exchange that pays winners? Yes, and the evidence for that is strong. Is it free of problems? No, and you should know what they are before you deposit.

Legit and unrestricted are two different questions. Most of the confusion online comes from mixing them up.

What Is Polymarket, and How Does It Actually Work?

Polymarket is an exchange where you buy and sell Yes/No contracts on real-world outcomes: elections, Federal Reserve decisions, sports, award shows, ceasefire timelines. A Yes share pays $1 if the event happens and $0 if it doesn't. A share trading at 72 cents means the market collectively puts the outcome at about 72%.

There's no house on the other side of your trade. Polymarket runs a central limit order book, so you're matched against other traders, and prices move as people update on new information. Early Polymarket markets used an automated market maker. The platform moved to an order book as it scaled, and in April 2026 it shipped a rebuilt exchange, CTF Exchange V2, audited by Cantina and Quantstamp.

The international platform runs on the Polygon blockchain. Since the April 2026 upgrade, trades settle in pUSD, a dollar stablecoin backed 1:1 by USDC that replaced the older bridged USDC.e. For the user, balances still show in plain dollars.

Is Polymarket One Platform or Two?

It's two, and this detail matters for almost every "is it legit" question.

Polymarket international (polymarket.com) is the original, globally facing, onchain exchange. It's non-custodial, it doesn't require ID to connect a wallet, and it does not serve US residents.

Polymarket US is a separate, CFTC-regulated exchange operated by QCX LLC. It requires full identity verification (name, date of birth, address, government ID, selfie), funds by card or Apple Pay as well as crypto, and runs under a federal rulebook. Our KYC comparison covers the verification split in detail.

Is Polymarket Regulated, and What Happened With the CFTC?

The record here is long. It's clearest in order.

Why Did the CFTC Fine Polymarket in 2022?

On January 3, 2022, the CFTC ordered Blockratize, the company behind Polymarket, to pay a $1.4 million civil penalty. The charge was offering event-based binary options without registering as a designated contract market or swap execution facility. Polymarket had been listing these markets since mid-2020.

The penalty was reduced because of what the CFTC called Polymarket's "substantial cooperation." The order also required Polymarket to wind down non-compliant markets, which meant blocking US persons from the international platform.

That settlement is about registration and jurisdiction. It did not allege fraud, theft of customer funds, or unpaid winnings. It's also the single biggest reason the "is Polymarket legit" question kept coming up for years.

Was Polymarket Investigated by the FBI?

Yes. On November 13, 2024, a week after the US presidential election, FBI agents searched CEO Shayne Coplan's New York apartment and seized his phone and electronics, CNBC reported. Coplan was not arrested. The probe, led by federal prosecutors in Manhattan, focused on whether US users had been accessing the platform despite the 2022 order.

Both investigations closed without charges. In July 2025, the Justice Department and the CFTC each ended their probes, CNBC reported on July 15, 2025. For a legitimacy question, that result is important: the most serious federal scrutiny Polymarket has faced ended with no charges.

How Did Polymarket Get Back Into the US?

It bought a license instead of fighting the old order. The CFTC designated QCX LLC as a contract market on July 9, 2025. On July 21, 2025, Polymarket announced it acquired QCX and its clearinghouse, QC Clearing, for $112 million.

The rollout from there:

1. September 2, 2025: CFTC staff issued a no-action letter for QCX.
2. November 12, 2025: Polymarket US opened an invite-only beta.
3. November 24, 2025: the CFTC approved an amended designation allowing intermediated access through brokers, and QCX began operating as "Polymarket US."
4. December 3, 2025: the iOS app launched publicly, starting with sports and a waitlist.
5. May 12, 2026: Polymarket removed the waitlist for iOS users.

As of September 2026, iOS access is fully open. Android and web access were still rolling out according to third-party trackers, and Polymarket hasn't published a formal launch announcement for either. Our US setup guide walks through signup and funding.

Separately, on April 28, 2026, Polymarket asked the CFTC to let US users onto its main international exchange too, CoinDesk reported. No public decision had been announced as of late September 2026.

Which US States Are Fighting Polymarket?

This is where the regulatory picture is least settled, and it mirrors the fight Kalshi is in. Federal regulators have backed prediction markets. Several states argue sports and election contracts are unlicensed gambling.

• Nevada: the Gaming Control Board sued in January 2026. A state judge issued a preliminary injunction against Polymarket US on May 29, 2026, covering sports, election, and entertainment contracts. Nevada is the one state where a court order clearly blocks Polymarket US.
• Massachusetts: Polymarket sued the state attorney general in federal court in February 2026 to block enforcement before it started.
• Minnesota: a 2026 state law would have made operating a prediction market a felony from August 1. A federal judge blocked it on July 27, 2026, in a case brought by the CFTC, Kalshi, and Polymarket US together, MPR reported.
• New York: Governor Hochul and Attorney General James sued Polymarket US on September 24, 2026, alleging illegal gambling, two months after suing Kalshi, CNBC reported. Polymarket filed its own countersuit.
• Other states: Connecticut, Tennessee, Illinois, Arizona, and Ohio have issued cease-and-desist letters to prediction market operators, according to state-by-state trackers.

The federal regulator is on the platforms' side. Under Chairman Michael Selig, the CFTC has filed briefs supporting federal authority over event contracts and has sued several states, including Arizona, Connecticut, Illinois, New York, and Wisconsin, to stop state enforcement.

The courts are split. On August 28, 2026, the Ninth Circuit ruled against Kalshi in Nevada, finding that sports contracts are likely bets states can regulate, CNBC reported. That conflicts with an April 2026 Third Circuit ruling in Kalshi's favor, which makes a Supreme Court case likely.

Whatever the Court decides will apply to Polymarket US and Kalshi alike. Our regulation explainer tracks the full state-by-state fight.

Where Is Polymarket Blocked Outside the US?

Polymarket's own geographic restrictions page lists 39 blocked countries, including the US (for the international platform), the UK, France, Germany, Italy, Belgium, the Netherlands, Australia, and Japan. Singapore, Poland, Thailand, and Taiwan are "close-only," meaning existing users can exit positions but not open new ones.

Some of those blocks came from national gambling regulators. Switzerland blacklisted Polymarket in November 2024, Poland and Belgium followed in January 2025, and Singapore and Thailand moved against it the same month. Portugal and Hungary acted in January 2026.

France went furthest. After Polymarket geoblocked French users in November 2024, France's gambling authority ordered internet providers to block the site entirely on July 17, 2026, and Polymarket said it would challenge that order. Italy's regulator has blocked, reinstated, and re-blocked access, most recently in July 2026. Our international regulation guide covers each jurisdiction.

Does Polymarket Actually Pay Out?

This is the practical version of "is it legit," and the answer is yes. We found no documented case of Polymarket refusing to pay a winning position that resolved in the holder's favor.

On the international platform, once a market resolves, winning shares redeem for $1 each in the wallet that holds them. No withdrawal request needs approving and no support ticket stands between you and the money. The smart contract pays according to the resolved outcome.

That design has a limit. The payout is automatic, but the outcome still has to be decided by someone, and that's where Polymarket's real controversies come from. The dispute section below covers them.

Who Holds Your Money on Polymarket?

On the international platform, you do. It's non-custodial: your funds sit in a wallet you control, including the wallet Polymarket creates for you if you sign up with email or Google through a login provider. Polymarket can't freeze or spend those funds the way a traditional broker could.

That puts the security responsibility on you. Lost keys, a compromised email login, or a signature on a phishing site are your problem to prevent, not something a bank will reverse. Polymarket US works differently. As a regulated, intermediated exchange, it runs accounts under CFTC customer-protection rules, closer to how Kalshi handles custody.

What Does Polymarket Charge?

Polymarket used to be known as the fee-free prediction market. That's no longer true. Between January and March 2026, it rolled out taker fees across nearly every category, per its trading fees page (updated July 10, 2026).

The formula is shares × category rate × price × (1 − price), which peaks at a 50-cent contract and shrinks toward the extremes:

Makers who post resting limit orders pay nothing and earn a rebate of 15% to 25% of taker fees, depending on category. Polymarket doesn't charge deposit or withdrawal fees, though card on-ramps and network costs can apply. Crypto markets now carry the same fee curve shape as Kalshi's. Our fee comparison lines up all five platforms.

Is Polymarket's Trading Volume Real? What the Wash Trading Research Shows

This is one of the most searched parts of the record, and one of the most misreported. Wash trading means one trader, or a cluster of linked wallets, trading against themselves to inflate volume without taking real risk. Our wash trading explainer covers the mechanics. Here's what has been found on Polymarket specifically.

What Did Researchers Find During the 2024 Election?

In October 2024, with Trump trading around 67% on Polymarket, two blockchain analytics firms looked at the presidential market. Chaos Labs estimated about one-third of that market's volume was wash trading. Inca Digital estimated real volume around $1.75 billion against the roughly $2.7 billion then reported, Fortune reported on October 30, 2024.

Polymarket responded that its terms of use prohibit market manipulation. The presidential market ended with about $3.6 billion in volume, and it resolved correctly for Trump on November 6, 2024.

What Did the Columbia University Study Find?

The most detailed estimate came in November 2025. Researchers at Columbia University and Barnard College (Allen Sirolly, Hongyao Ma, Yash Kanoria, and Rajiv Sethi) released a working paper, "Network-Based Detection of Wash Trading," covering Polymarket data from late 2022 through mid-October 2025. It had not been peer-reviewed at release.

Their algorithm looked for closed clusters of wallets that mostly traded with each other and repeatedly opened and closed positions. The headline findings, per CoinDesk and Decrypt:

• About 25% of historical volume, roughly $4.5 billion, showed wash trading patterns.
• About 14% of 1.26 million wallets were flagged.
• The activity rose from July 2024, peaked near 60% of weekly volume in December 2024, fell below 5% around May 2025, and was back near 20% in early October 2025.
• By category, sports markets were the most affected (about 45% all-time), followed by elections (17%), politics (12%), and crypto (3%).

The researchers pointed to three likely drivers: no fees at the time, no identity checks on the international platform, and widespread expectation of a token airdrop that might reward trading activity. Lead author Allen Sirolly said the team found no evidence that the exchange itself was involved.

Is Polymarket Volume Double Counted?

Partly, but not by Polymarket. In December 2025, Paradigm researcher Storm Slivkoff showed that some third-party dashboards were summing both sides of every onchain fill, which roughly doubled Polymarket's volume on those sites. Several data providers said they would fix it.

Polymarket's data team said its own site reports taker-side notional volume, the same convention Kalshi uses, and was never double counted. Some critics also noted that Paradigm is a Kalshi investor. For readers, the takeaway is simple: compare like-for-like figures, and be skeptical of any dashboard that doesn't state its method. Our guide to volume figures explains what the numbers do and don't capture.

Has Polymarket Done Anything About Wash Trading Since?

Yes. Two structural changes raised the cost of wash trading in 2026, whether or not that was the stated purpose.

First, taker fees. The Columbia researchers named zero fees as a driver, and since early 2026 a wash trade costs real money on every round trip in every category except geopolitics. Second, Polymarket US operates under CFTC rules, where wash sales are illegal under Section 4c(a) of the Commodity Exchange Act. Its market integrity program uses full KYC, trade surveillance partners, a real-time control desk, and a regulatory services agreement with the National Futures Association.

A July 2026 CNBC analysis found a separate, related pattern. About 70% of closed Polymarket markets traded under $10,000, and bots accounted for more than 80% of volume in those small markets. That's bot concentration rather than wash trading, but it points the same way: headline volume says little about any single small market.

No newer academic estimate of the wash trading share since fees arrived had been published as of September 2026, and no regulator has brought a wash trading case against Polymarket.

Is Wash Trading Just a Polymarket Problem?

No. It's an industry-wide growing pain, and any exchange with volume incentives is exposed to it. The most recent allegations, in the week of September 20, 2026, were aimed at Kalshi.

A trader flagged Kalshi's ETH perpetual contract for $539 million in 24-hour volume against about $3.1 million in open interest. Repeated identical $5,500 trades made up as much as 58% of volume on some days, CoinDesk reported. Kalshi's crypto lead denied wrongdoing, pointed to fair-access rules, and said Kalshi uses the same volume reporting convention as Polymarket. No regulator has accused Kalshi either.

The practical lesson applies to both platforms: volume is a signal to check, not a fact to trust. Our guide to spotting manipulation walks through the tells.

How Does Polymarket Decide Who Wins, and Has It Ever Gotten It Wrong?

Most Polymarket markets resolve through UMA's optimistic oracle. Someone proposes an outcome and posts a bond (currently $750). If nobody disputes it within a two-hour window, it finalizes. If someone disputes it, there's a debate period and, if the dispute holds, a vote by UMA token holders, per Polymarket's resolution docs.

For most markets this runs smoothly. Polymarket says only about 0.2% of markets ever go to a token-holder vote. Price-based crypto markets resolve through Chainlink data feeds instead, and since August 2026 Polymarket's short-duration crypto up/down markets settle on a Chainlink time-weighted average price.

The disputes that do escalate have produced Polymarket's most serious criticism. Here are the major ones.

Which Polymarket Resolutions Have Been Disputed?

Barron Trump and the DJT token (June 2024). UMA voters resolved a roughly $1 million market "No." Polymarket publicly said "UMA got this resolution wrong" and refunded Yes holders itself, The Block reported. That's one of the few times the platform paid out of pocket to correct an outcome.

Venezuela's election (August 2024). The market on the July 2024 election resolved to opposition candidate Edmundo González, even though the market's stated primary source, official Venezuelan government information, declared Nicolás Maduro the winner. Critics argued voters overrode the written rules. Supporters argued the official count wasn't credible.

The Ukraine minerals deal (March 2025). A roughly $7 million market resolved "Yes" before any deal was signed. One UMA holder controlling about 5 million tokens across three accounts cast roughly a quarter of the votes, CoinDesk reported. Polymarket called the situation "unprecedented" and said it wasn't a market failure, and it didn't issue refunds.

Zelenskyy's suit (July 2025). A market worth well over $160 million asked whether Ukraine's president would wear a suit before July. After he appeared at the NATO summit in a black jacket, the market was first proposed "Yes," then resolved "No" after disputes, CoinDesk reported. The case became the standard example of how subjective wording can make a market hard to resolve.

Strategy's bitcoin sale (May 2026). A market on whether Strategy (formerly MicroStrategy) would sell bitcoin resolved "No" after a UMA vote, even though a June 1 SEC filing later showed the company sold 32 BTC in late May. In July 2026, a group of traders sued Polymarket and Coplan in New York state court for breach of contract. They allege 1,868 traders lost about $6.5 million, The Defiant reported. The case is ongoing.

Is UMA's Voting System Being Fixed?

It's changing. In August 2025, UMA governance passed a proposal restricting who can propose Polymarket outcomes to a whitelist of about 37 addresses, including Risk Labs and Polymarket staff and users with a long, accurate proposal record, The Block reported. Anyone can still dispute a proposal.

Scrutiny has continued. A Wall Street Journal investigation in May 2026 reported that disputes in 2026 had already passed the full-year 2025 total, and that a small group of large wallets cast most votes in many disputes. UMA said it had "never seen any credible evidence" of manipulation.

Kalshi's model is the useful contrast. It resolves markets through its own staff and an Outcome Review Committee under a CFTC-filed rulebook, which trades decentralization for one accountable decision-maker.

Kalshi has had its own settlement fights, including a January 2026 reversal on unpaid NFL contracts after user backlash and a class action over a "death carveout" rule. Neither model has eliminated disputes. Each fails differently, and knowing which one you're trading under is part of reading the market rules before you enter.

Has Polymarket Been Hacked?

Polymarket's core exchange smart contracts have never been reported exploited. Users have lost funds through attacks around the edges: login providers, phishing, and, once, the website itself.

Sources: CoinDesk (December 2025), CoinDesk (May 2026), TechCrunch and CoinDesk (June 2026).

The June 2026 incident is the one that matters most for a legitimacy question, because it hit the official site rather than a look-alike. Polymarket's pledge to make affected users whole is the right response. The broader pattern points to how to protect yourself: use a hardware wallet or a wallet extension instead of email-only login for meaningful balances, never click trading links posted in comments, and check the domain before you sign anything.

Has Anyone Been Caught Insider Trading on Polymarket?

Yes, and Polymarket's onchain transparency is part of how they were caught. Because every trade on the international platform is public, unusual bets before major news are visible to anyone, including journalists and prosecutors.

The Nobel Peace Prize (October 2025). Odds on María Corina Machado jumped from about 3.6% to over 70% roughly 11 hours before the announcement, and Norway's Nobel Institute opened an inquiry into a possible leak, CoinDesk reported.

Israeli military operations (February 2026). Israel indicted a reservist and a civilian for allegedly using classified information to bet on military operations, earning roughly $150,000, The Times of Israel reported.

Maduro's removal (April 2026). The CFTC and federal prosecutors in Manhattan charged a US Army master sergeant with buying more than 436,000 Yes shares in a "Maduro out by January 31, 2026" market in the days before Maduro's January 3 removal. He's alleged to have made more than $404,000 on about $33,000 in trades.

Polymarket tightened its rules in March 2026, publishing updated integrity rules for both the international platform and Polymarket US that ban trading on stolen confidential information, illegal tips, or events the trader can influence. The CFTC's February 2026 insider-trading advisory, which applies to every regulated exchange, cited two cases, both on Kalshi, which shows this isn't unique to one platform either.

What Are the Latest Polymarket Controversies (September 2026)?

The most recent headlines are about Polymarket's compliance and marketing practices, not about whether it pays traders. They're serious, and they're still developing.

The Wall Street Journal compliance report (September 20, 2026). The WSJ reported that Polymarket US faced a stolen-card fraud attack worth at least $10 million in February 2026. The report also said Coplan pushed growth over internal compliance concerns and that the US compliance chief resigned in April. The CFTC has opened an investigation, according to The Block, which summarized the report. Polymarket said it is "focused on growing responsibly." These are reported allegations, not findings.

Influencer marketing (June 2026). A separate WSJ report alleged Polymarket paid creators to post staged trades and winnings. The National Association of Consumer Advocates sued, a consumer class action followed in September 2026, and the CFTC was reported in June to be investigating Polymarket's marketing, CNBC reported. Polymarket said it was conducting a comprehensive audit of active promotional content.

New York's lawsuit (September 24, 2026). Covered in the state section above. It follows New York's July suit against Kalshi, so it's part of an industry-wide state push rather than a Polymarket-only action.

None of these alleges that Polymarket took customer funds or refused to pay winners. They're about how a fast-growing exchange handles fraud screening, compliance staffing, and advertising. Those problems matter, and the CFTC investigation is the one to watch. They're also the kind of scaling problems regulated exchanges have worked through before.

Who Is Behind Polymarket, and Is It Financially Stable?

Polymarket has some of the most established backers in the industry, which is strong evidence it's legitimate. Shayne Coplan founded it in 2020.

• Intercontinental Exchange, the owner of the New York Stock Exchange, agreed on October 7, 2025 to invest up to $2 billion at roughly an $8 billion pre-money valuation, and added a $600 million direct investment in March 2026.
• 1789 Capital invested in August 2025, and Donald Trump Jr. joined Polymarket's advisory board.
• In August 2026, Polymarket was reported to be seeking about $1 billion at a valuation above $20 billion, CNBC reported. That round hadn't been confirmed as closed at the time of writing.

Its distribution partnerships point the same way. X named Polymarket its official prediction market partner in June 2025. The NHL signed multiyear deals with both Polymarket and Kalshi in October 2025. Google began showing Polymarket and Kalshi odds in Search and Google Finance in November 2025, and UFC parent TKO signed a multiyear integration deal the same month.

Polymarket's CMO has confirmed a POLY token and airdrop are planned. As of September 2026, no launch date or eligibility rules have been announced. Treat any site claiming to offer the airdrop now as a scam.

How Big Is Polymarket Compared to Kalshi?

Polymarket is the largest crypto-native prediction market, but it's no longer the largest overall. It traded about $21.5 billion in 2025, per Keyrock and Dune data, and set a single-day record of about $425 million on February 28, 2026.

Kalshi passed Polymarket in monthly volume in March 2026, and the gap has widened. In August 2026, Kalshi traded about $37.2 billion against about $8.2 billion for Polymarket's international and US platforms combined, The Block reported. Much of Kalshi's lead comes from US sports contracts.

For a trader, headline volume matters less than depth in the specific market you want. Polymarket often still carries deep liquidity on geopolitical, international-election, and crypto markets that US-focused venues list thinly or not at all. Our liquidity comparison breaks this down by category.

How Does Polymarket Compare to the Other Four Platforms?

PredictionHero tracks five platforms, and they differ in structure, not just branding. None of the differences below is a legitimacy ranking.

Kalshi was built for US compliance from day one, which is why it never had a 2022-style enforcement moment. Polymarket built global liquidity first and added US compliance through an acquisition.

Both now answer to the same federal regulator for their US products, and both are in the same state-court fight. Our head-to-head Polymarket vs. Kalshi comparison and Kalshi review go deeper.

Limitless and Predict.Fun both run order books with their own incentive designs; our Limitless explainer covers its hybrid model for short-duration crypto contracts. Opinion's macro focus means it sometimes lists economic-data contracts in more granular form than the larger venues, covered in our Opinion guide.

So, Should You Use Polymarket?

Once the scam question is settled, the useful question is whether Polymarket fits what you're trying to do.

Polymarket is a strong fit if you're outside the US and in a country where it's available, you want deep markets on global politics, geopolitics, or crypto, and you're comfortable managing a crypto wallet. It's also a real option in the US through Polymarket US if you're on iOS and outside Nevada. Our setup guide walks through eligibility.

Consider Kalshi instead if you're in the US and want web or Android access, bank-transfer funding with no crypto step, or a platform whose resolution decisions come from an accountable, CFTC-filed committee rather than a token vote.

Whichever platform you use, read each market's resolution rules before you trade, especially for subjectively worded questions, and check what happens if the event is cancelled or postponed. Treat high volume as a claim to check, not a guarantee of depth. Size positions to what you can afford to lose.

Comparing the same event across Polymarket, Kalshi, Limitless, Predict.Fun, and Opinion on PredictionHero is the fastest way to see where prices agree, where one venue is thin, and where the odds differ enough to matter.

Sources

• CFTC. "CFTC Orders Event-Based Binary Options Markets Operator to Pay $1.4 Million Penalty." January 3, 2022. cftc.gov
• CNBC. "FBI raids Polymarket CEO's home, seizing phone, electronics." November 14, 2024. cnbc.com
• CNBC. "DOJ, CFTC end Polymarket investigations." July 15, 2025. cnbc.com
• PR Newswire. "Polymarket Acquires CFTC-Licensed Exchange and Clearinghouse QCEX for $112 Million." July 21, 2025. prnewswire.com
• CFTC. "Polymarket US Amended Order of Designation." November 2025. cftc.gov
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• Covers. "Polymarket Removes Waitlist, Launches for American iOS Users." May 12, 2026. covers.com
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• Nevada Attorney General. "Preliminary Injunction in Prediction Market Case." May 2026. ag.nv.gov
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• Polymarket Docs. "Resolution." docs.polymarket.com
• Fortune. "Election betting site Polymarket is rife with fake 'wash' trading, researchers say." October 30, 2024. fortune.com
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• CoinDesk. "Polymarket, UMA communities lock horns after $7M Ukraine bet resolves." March 27, 2025. coindesk.com
• CoinDesk. "Polymarket embroiled in $160M controversy over whether Zelensky wore a suit at NATO." July 7, 2025. coindesk.com
• The Block. "UMA restricts Polymarket proposals to whitelisted addresses." August 2025. theblock.co
• The Defiant. "Traders sue Polymarket CEO Coplan over Strategy market decision." July 2026. thedefiant.io
• CoinDesk. "Polymarket points to third-party login tool after users report account breaches." December 24, 2025. coindesk.com
• CoinDesk. "ZachXBT flags $520K Polymarket exploit on Polygon; team says funds are safe." May 22, 2026. coindesk.com
• TechCrunch. "Polymarket says hackers stole users' funds." June 25, 2026. techcrunch.com
• CoinDesk. "Polymarket hack updated to $3.1 million." June 27, 2026. coindesk.com
• CoinDesk. "Norwegian officials probe major Polymarket bets on Nobel Peace winner." October 11, 2025. coindesk.com
• The Times of Israel. "Two indicted for using classified info to place online bets on military operations." February 12, 2026. timesofisrael.com
• CFTC. Press Release 9217-26 (insider trading charges, Maduro market). April 23, 2026. cftc.gov
• CFTC. "CFTC Enforcement Division Issues Prediction Markets Advisory." February 25, 2026. cftc.gov
• Polymarket. "Market Integrity Rules." integrity.polymarket.us
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• CNBC. "CFTC is conducting an investigation into Polymarket, source says." June 26, 2026. cnbc.com
• Intercontinental Exchange. "ICE Announces Strategic Investment in Polymarket." October 7, 2025. ir.theice.com
• Intercontinental Exchange. "Intercontinental Exchange Announces New $600 Million Investment in Polymarket." March 27, 2026. ir.theice.com
• CNBC. "Polymarket seeks fundraising round at more than $20 billion valuation." August 4, 2026. cnbc.com
• The Block. "Kalshi and Polymarket volume falls in August." September 2, 2026. theblock.co

PredictionHero aggregates publicly available prediction market data for informational purposes only. This is not financial advice. Prediction markets may not be available in all jurisdictions.