Can You Sue a Prediction Market? Trader Remedies When Event Contracts Settle Wrong

Can you sue a prediction market when it settles a market wrong? Yes, but the path is far narrower than most traders assume. In July 2026, two settlement disputes put the question in front of the whole industry at once. Kalshi paid out a market asking whether Brad Pitt attended the World Cup Final, even though the sightings appear to trace to on-air and live-blog misidentifications. Polymarket’s platform resolved a market on whether Strategy would sell bitcoin against the traders who bet it would, because the company’s SEC disclosure landed one day after the market’s window closed.¹

The two disputes look alike from the outside. Legally, they are opposites. One is a fight about what the contract actually asked. The other is a fight about when an event counts as having happened. And only one of them has produced a lawsuit. That asymmetry is not an accident. It is a map of what remedies actually exist in this market structure, and where they stop.

This article walks through the five remedies traders have when an event contract settles incorrectly, uses the two July disputes to show how each one plays out, and explains why state gambling law, the tool most people reach for first, is mostly off the table.

Key Takeaways

• Exchanges grade their own markets. On both Kalshi and Polymarket’s U.S. exchange, outcome review runs at the exchange’s sole discretion, its determination is final, and neither rulebook we reviewed gives customers a way to object to a settlement.

• Federal suits require bad faith. Section 22 of the Commodity Exchange Act lets traders sue a CFTC-designated exchange for actual damages only on proof of “bad faith” plus causation, a bar an honest misreading of a source does not clear.²

• State gambling regulators are largely preempted. The Third Circuit held in April 2026, affirming a preliminary injunction, that the Commodity Exchange Act preempts state gaming regulation of sports-related event contracts listed on CFTC-licensed exchanges, while preserving common-law fraud and negligence claims.

• The gambling-law route is being tested anyway. Kentucky’s attorney general has sued Polymarket’s operators in state court under the state’s Loss Recovery Act, seeking treble the money lost.

• Read the contract terms, not the market title. The Brad Pitt market’s filed terms asked whether a listed Source Agency reported attendance, not whether Pitt actually attended, and it settled yes.

Can You Sue a Prediction Market for a Wrong Settlement?

A trader can sue a federally regulated prediction market, but Congress built the cause of action deliberately narrow. Section 22 of the Commodity Exchange Act creates a private right of action against a CFTC-designated exchange for actual damages when the exchange fails to enforce its own rules, or violates the Act in enforcing them. The trader must prove the exchange acted in “bad faith” and that the failure or action caused the loss.²

That bad-faith requirement is the wall most settlement grievances die against. A market graded on a defensible reading of ambiguous terms, or on an honest misreading of a source, does not clear it. The exchanges reinforce the statute with exculpation clauses in their rulebooks that cut off liability for anything short of gross negligence, and Polymarket’s U.S. rulebook adds hard dollar caps on what the exchange can owe a single participant, $2,500 a day, $5,000 a month, and $50,000 a year, though the caps expressly do not reach a Commodity Exchange Act violation.³

A prediction market is an exchange where traders buy and sell event contracts, positions that pay out based on real-world outcomes. An event contract is a derivative that pays out on whether a specified event occurs, and on a CFTC-designated exchange it trades under filed contract terms that control settlement. That regulatory posture is what makes prediction markets like Kalshi and Polymarket’s U.S. exchange different from offshore betting sites, and it is also what makes suing them hard. The federal regime channels disputes into the exchange’s own machinery first.

If you traded a market you believe was mis-settled, pull the filed contract terms first: your claim lives or dies on them, not on the market title.

What Remedies Do Traders Actually Have?

Traders have five remedies when a prediction market resolves incorrectly, and they run out fast. The ladder goes from the exchange’s own review to a CFTC complaint, and each rung has a structural limit worth understanding before money is on the line.⁴

First, the exchange’s own outcome review. Kalshi’s rulebook gives the exchange “sole discretion” to interpret a contract’s terms and makes outcome determinations “final,” and Polymarket’s mirror rule states that “Determinations made by the Company are final.” A trader cannot start that review and cannot appeal it. Kalshi gives traders fifteen minutes to flag an order or trade error, and Polymarket commits only to reviewing an error notification by the next business day. Nothing comparable exists for how a market was graded.⁵

Second, arbitration. Kalshi’s rulebook makes it mandatory, loser-pays, and administered by Kalshi itself. The exchange collects the filing fee and convenes the panel, and if the seated arbitrators do not satisfy the rulebook’s qualification requirements, a committee of Kalshi’s own board, made up only of its independent public directors, may act as the arbitration panel itself, so long as it has no direct interest in the matter.⁶ Polymarket’s U.S. rulebook routes claims against the exchange to JAMS through its Terms of Use, and a trader who brings a claim against the exchange and loses pays the exchange’s defense costs above $50,000.⁷ Federal law puts the dispute-resolution duty on the exchange itself and prescribes no independent industry-wide forum, so nothing here resembles the arbitration forum FINRA runs for securities customers.⁸ Each exchange points traders at its own paper.

Third, the federal suit under Section 22 of the Commodity Exchange Act, gated by the bad-faith requirement. Fourth, common-law fraud and negligence claims, which survive federal preemption and are discussed below. Fifth, a complaint to the CFTC, which can punish but does not compensate. When the CFTC fined Polymarket’s operator $1.4 million in 2022 for offering unregistered event markets, customers got their open positions redeemed and nothing more.⁹

If your loss traces to a settlement call rather than a trade error, assume the exchange’s internal process will not reopen it, and price the fee-shifting risk before you arbitrate.

The Brad Pitt Market: When the Title Is Not the Contract

The Kalshi Brad Pitt dispute is a “title versus terms” problem, and it is the cleanest illustration in the industry today of why reading filed contract terms matters more than reading market titles. The market title asked whether Pitt attended the 2026 World Cup Final. The contract’s filed terms made the underlying something else entirely: not whether he attended, but whether a listed Source Agency reported him present, and any one report sufficed.¹⁰

The market’s own rules spell the reporting standard out: “Attendance is confirmed if the person is reported present at the event by any Source Agency, including social media posts by the person themselves.”¹⁰ That gap was not hypothetical. During the July 19 final, a FOX broadcast announcer misidentified Matt Damon as Pitt on air and was corrected moments later.¹¹ NBC Sports’ live blog listed Pitt in its celebrity roundup during the match, and that entry remained online uncorrected in late July. The Hollywood Reporter’s post-match attendee roster did not include him and attributed the Pitt mention to a broadcaster’s error, and Fox News’s pre-kickoff sightings roundup placed him only at earlier matches in the tournament.¹² The contract’s listed Source Agencies include NBC. Kalshi has not publicly identified which report it relied on. If it treated the NBC Sports entry as an NBC report, the market paid out on an apparent misidentification that a listed source repeated. The market settled yes at $1.00.¹³

Traders think they are betting on a fact. They are actually betting on media coverage of the fact. Kalshi’s own member agreement puts traders on notice that each contract’s specific rules dictate settlement, payout, and outcome determination.¹⁴ The market title is not the operative term.

Notice what the Pitt controversy has not produced so far: a case. The traders organizing over it are still at an interest-list stage, and the unattributed website soliciting their complaints itself says that no lawsuit, lawyer, or class has been confirmed.¹⁵ The short remedies ladder for prediction-market traders is why.

“When no objection window exists and the forum belongs to the exchange, a mis-graded market generates complaints, not lawsuits.” ---Chanté Eliaszadeh, Principal Attorney, Astraea Counsel APC

If a market’s title and its filed terms can diverge on the question you care about, the terms win, so read them before you trade, not after settlement.

The Strategy Bitcoin Market: When Timing Decides Everything

The Polymarket Strategy dispute is the mirror image of the Kalshi Brad Pitt dispute: an “occurrence versus confirmation” problem rather than a “title versus terms” fight, and it did produce a real case. The market promised to resolve yes if Strategy sold any bitcoin by the deadline. Strategy’s SEC filing disclosed a late-May sale, but the disclosure landed June 1, one day after the window closed, and Polymarket’s added guidance required confirmation inside the window.¹⁶ The event arguably happened in time. The proof did not.

In July 2026, two traders sued Polymarket and its executives in New York state court for breach of contract and deceptive practices over that call.¹⁷ A putative federal class action filed in March, Risch v. KalshiEX, presses a similar grievance about how Kalshi settled a market on Iran’s Supreme Leader.¹⁸ These are contract-interpretation fights, not fact fights, and both sides have real arguments. The difference between the Pitt dispute and the Strategy dispute is instructive: a claim survives when it can be framed as the exchange breaking its own stated rules, rather than as the exchange reading an ambiguous world badly.

If your dispute turns on the exchange changing or adding resolution guidance mid-market, preserve the original rule text immediately, because that language is the whole case.

Does Gambling Law Apply to Prediction Markets?

Mostly not, after April 2026, and this is the answer that surprises traders most. In KalshiEX LLC v. Flaherty, the Third Circuit, affirming a preliminary injunction, ruled for the prediction market against state gaming regulators. “We hold that both field and conflict preemption apply,” the court wrote of the sports-related event contracts before it, reasoning that the preempted field is the regulation of trading on a designated contract market rather than gambling. The same decision read the Act’s savings clause to preserve state common-law actions like fraud and negligence.¹⁹ That is the lane left open for private plaintiffs, and it is the lane the New York traders suing Polymarket over the Strategy market are using.

The gambling-law route is being tested anyway, from the government side. Kentucky’s attorney general has sued Polymarket’s operating entities in state court under Kentucky’s Loss Recovery Act, a gambling loss-recovery statute, seeking treble the value of the money lost.²⁰ That suit will meet the same preemption wall from the other direction, and its outcome will tell state regulators whether any gambling-law theory survives contact with a CFTC license.

The comparison worth holding onto: a Commodity Exchange Act claim reaches the exchange only on bad faith, while a common-law negligence or fraud claim carries ordinary state-law standards but must survive preemption, exculpation clauses, and liability caps. Neither is easy. They fail differently.

If you are building a state-law theory against a federally licensed exchange, frame it in common-law fraud or negligence, because the gaming-regulation frame is presumptively preempted.

What Regulators Are Doing About Settlement Disputes

The CFTC has started pressing on settlement integrity itself. A March 2026 staff advisory tells exchanges that staff expects them to identify the specific settlement sources for an event contract up front and to assess how resistant those sources are to manipulation.²¹ Senator Richard Blumenthal has pressed the agency on what he calls “failures of dispute resolution mechanisms” on event-contract platforms.²²

Decentralized resolution has its own version of the problem. Polymarket’s legacy oracle lets UMA token holders vote on disputed outcomes. A large UMA holder was reported to have swung the resolution of a $7 million market in March 2025, in what Polymarket called an “unprecedented situation,” and Polymarket declined refunds on the stated ground that the episode “wasn’t a market failure.”²³ When the dispute system works as designed and still gets the outcome wrong, that is not a bug in the system. It is the system.

The fixes are starting unevenly. Polymarket’s July 2026 rulebook update adds a tiered source hierarchy for resolution, while defining the exchange itself as the “Source Agency.”²⁴ The harder pieces, customer objection windows and independent outcome review, are still missing on both major U.S. venues.

If your platform lists event contracts, the staff advisory’s stated expectations, named settlement sources and a manipulation-resistance assessment, are the baseline to build your settlement architecture against.

What Traders and Platforms Should Do Now

For prediction-market traders, three immediate steps. Before trading any event contract, pull the filed contract terms and identify the settlement sources, because the title is marketing and the terms are the deal. Screenshot the market rules and any resolution guidance the day you trade, since mid-market guidance changes are exactly what the pending lawsuits turn on. And calendar the exchange’s error-notice windows, which run short, because a missed window on an order or trade error is unrecoverable.

For platforms, the next two quarters are the window to get ahead of this. The CFTC staff advisory already tells designated exchanges what the Division of Market Oversight expects on source identification and manipulation resistance.²¹ Building a customer-initiated objection window with a defined evidentiary standard would cost little, would answer the loudest structural criticism in the pending disputes, and would convert settlement controversies from public grievances into administrable records. Platforms that wait for the CFTC or a court to force the issue will build the same machinery later, on worse terms.

Longer term, the market structure question is whether event-contract dispute resolution stays inside each exchange or migrates to something independent. Securities customers got FINRA arbitration. Event-contract customers currently get the exchange’s own paper. Which way that resolves will shape how much institutional money trusts these venues.

If your company operates or is building an event-contract venue, treat settlement-dispute architecture as a regulatory expectation and a litigation exposure, not a product afterthought.

The Bottom Line

Prediction markets are good at pricing uncertainty and bad at admitting their own. The remedies ladder is real but short: exchange review the trader cannot initiate, arbitration on the exchange’s terms, a federal claim gated by bad faith, common-law claims that survive preemption but meet exculpation clauses, and a regulator that punishes without compensating. The disputes worth watching, the New York traders’ suit against Polymarket, the Kalshi class action, and Kentucky’s treble-damages action, will mark out how much of that ladder actually bears weight.

Until then, the practical rule for traders is the one the Brad Pitt market taught in a single afternoon: you are not betting on the fact, you are betting on the contract’s definition of the fact. Astraea Counsel advises trading platforms, funds, and founders on event-contract regulation, CFTC compliance, and settlement-dispute strategy. If your platform or portfolio touches these markets, the time to understand the dispute architecture is before the disputed settlement, not after.

Related Resources

• The CLARITY Act (H.R. 3633) Explained: How It Would Split SEC and CFTC Jurisdiction
• CFTC Commodities Regulation for Crypto: Bitcoin, Ethereum, and Digital Assets
• Crypto Enforcement Tracker (2024-2026): SEC and CFTC Actions, Penalties, and the Atkins Reversal
• The SEC/CFTC Token Taxonomy: What the Five Categories Mean for Your Token

This article provides general information for educational purposes only and does not constitute legal advice. Prediction-market and event-contract regulation is evolving rapidly. Consult qualified legal counsel for advice on your specific situation.

Footnotes

1. CoinDesk, “Strategy Sold Bitcoin in Late May, and Told the Market in June. Here’s How Polymarket Bettors Are Fighting Over When It Counts” (June 2, 2026), available at https://www.coindesk.com/markets/2026/06/02/strategy-sold-bitcoin-in-late-may-and-told-the-market-in-june-here-s-how-polymarket-bettors-are-fighting-over-when-it-counts; Strategy Inc., Current Report (Form 8-K) (filed June 1, 2026), available at https://www.sec.gov/Archives/edgar/data/1050446/000119312526249768/mstr-20260530.htm; see also The Block, “Two Traders Sue Polymarket Over Disputed Resolution of Strategy Bitcoin Sale Market” (July 7, 2026) (market resolved no), available at https://www.theblock.co/post/407368/two-traders-sue-polymarket-strategy-bitcoin-sale. ↩

2. 7 U.S.C. § 25(b)(1), (b)(4) (Commodity Exchange Act § 22), available at https://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-title7-section25&num=0&edition=prelim. ↩ ↩²

3. Kalshi DCM Rulebook v1.28, Rule 11.3(a) (last visited July 28, 2026), available at https://kalshi-public-docs.s3.us-east-1.amazonaws.com/regulatory/rulebook/Kalshi%20DCM%20Rulebook%20v.1.28%20clean.docx.pdf; Polymarket US Rulebook, Ch. 11 (2026.07.02), available at https://polymarketexchange.com/files/legal/Polymarket%20US%20Rulebook%20(2026.07.02).pdf. ↩

4. For the authorities behind each rung: Kalshi DCM Rulebook v1.28, Rules 6.3, 7.1, 10.1(c), 11.3(d); Polymarket US Rulebook (2026.07.02), Rules 9.2, 10.4, Ch. 11; 7 U.S.C. § 25(b); KalshiEX LLC v. Flaherty, No. 25-1922 (3d Cir. Apr. 6, 2026); In re Blockratize, Inc., CFTC Docket No. 22-09 (Jan. 3, 2022). ↩

5. Kalshi DCM Rulebook v1.28, Rules 5.11(c), 6.3(c), 6.3(f), 7.1; Polymarket US Rulebook, Rules 5.7(b), 10.4 (2026.07.02). ↩

6. Kalshi DCM Rulebook v1.28, Rules 2.6(a), 10.1(c), 10.2, 10.5(a), 10.5(f), 11.3(d). ↩

7. Polymarket US Rulebook, Rule 9.2 and Ch. 11 (2026.07.02); Polymarket US Website Terms of Use (May 27, 2026) (JAMS administers the arbitration under its Comprehensive Arbitration Rules and Procedures), available at https://www.polymarketexchange.com/files/legal/latest/website-terms-of-use. ↩

8. 7 U.S.C. § 7(d)(14); 17 C.F.R. § 38.750 (Core Principle 14) (requiring each designated contract market to “establish and enforce rules regarding, and provide facilities for alternative dispute resolution as appropriate for, market participants and any market intermediaries”; the provision places the duty on the board of trade and does not prescribe the forum). ↩

9. In re Blockratize, Inc. (d/b/a Polymarket.com), CFTC Docket No. 22-09 (Jan. 3, 2022), available at https://www.cftc.gov/media/6891/enfblockratizeorder010322/download. ↩

10. Kalshi ATTEND product certification, 17 C.F.R. § 40.2(a) submission (Mar. 14, 2025), available at https://kalshi-public-docs.s3.us-east-1.amazonaws.com/regulatory/product-certifications/ATTEND.pdf; Kalshi market rules, KXWCATTEND-26JUL20-BRA (secondary rules) (“Attendance is confirmed if the person is reported present at the event by any Source Agency, including social media posts by the person themselves.”), available at https://api.elections.kalshi.com/trade-api/v2/markets/KXWCATTEND-26JUL20-BRA. ↩ ↩²

11. The Spun via Yahoo Entertainment, “Several Celebs Mistakenly Identified During World Cup Final” (July 2026), available at https://www.yahoo.com/entertainment/celebrity/articles/several-celebs-mistakenly-identified-during-030000532.html; Complex, “World Cup Broadcast Mixup” (July 2026), available at https://www.complex.com/sports/a/markelibert/pharrell-asap-rocky-world-cup-broadcast-mixup. ↩

12. NBC Sports, “Spain vs. Argentina Live Updates” (Celebrity watch entry) (July 19, 2026), available at https://www.nbcsports.com/soccer/live/spain-vs-argentina-live-updates-score-goals-highlights-stats-2026-fifa-world-cup-july-19; Fox News, “Brad Pitt, Tom Cruise, David Beckham Lead Star-Studded Celebrity Sightings at 2026 FIFA World Cup” (July 19, 2026), available at https://www.foxnews.com/entertainment/brad-pitt-tom-cruise-david-beckham-lead-star-studded-celebrity-sightings-2026-fifa-world-cup; The Hollywood Reporter, “World Cup Finals Star-Spotting: Matt Damon, Tom Cruise, Jay-Z, Beyoncé and Timothée Chalamet” (July 19, 2026) (attendee roster omitting Pitt), available at https://www.hollywoodreporter.com/tv/tv-news/world-cup-final-2026-celebrities-in-attendance-1236651733/. ↩

13. Kalshi API, market KXWCATTEND-26JUL20-BRA (result: yes; settlement $1.00), available at https://api.elections.kalshi.com/trade-api/v2/markets/KXWCATTEND-26JUL20-BRA. ↩

14. Kalshi Member Agreement v1.6 (last visited July 28, 2026), available at https://kalshi-public-docs.s3.us-east-1.amazonaws.com/regulatory/agreement/kalshi_member_agreement.pdf. ↩

15. Settle It by the Rules (trader-organizing website), available at https://settle-it-by-the-rules.sama1.chatgpt.site/ (last visited July 28, 2026). ↩

16. Crypto Briefing, “Polymarket Accused of Changing Settlement Rules to Void Winning Bet on Strategy Bitcoin Sale” (June 4, 2026), available at https://cryptobriefing.com/polymarket-accused-rewriting-rules-deny-payouts-confirmed-strategy-bitcoin-sale/. ↩

17. The Block, “Two Traders Sue Polymarket Over Disputed Resolution of Strategy Bitcoin Sale Market” (July 7, 2026), available at https://www.theblock.co/post/407368/two-traders-sue-polymarket-strategy-bitcoin-sale. ↩

18. Complaint, Risch v. KalshiEX LLC, No. 2:26-cv-02390 (C.D. Cal. filed Mar. 5, 2026), available at https://www.classaction.org/media/kalshiex-complaint.pdf. ↩

19. KalshiEX LLC v. Flaherty, No. 25-1922 (3d Cir. Apr. 6, 2026), available at https://www2.ca3.uscourts.gov/opinarch/251922p.pdf. ↩

20. Complaint, Commonwealth of Kentucky ex rel. Coleman v. QCX LLC, No. 26-CI-00696 (Ky. Franklin Cir. Ct. filed June 17, 2026); Ky. Rev. Stat. § 372.040 (authorizing a third person to sue the winner and “recover treble the value of the money or thing lost” where the loser has not sued within six months), available at https://apps.legislature.ky.gov/law/statutes/statute.aspx?id=35268; see Kentucky Attorney General press release, available at https://www.kentucky.gov/Pages/Activity-stream.aspx?n=AttorneyGeneral&prId=1791. ↩

21. CFTC Staff Letter No. 26-08 (Mar. 12, 2026), available at https://www.cftc.gov/csl/26-08/download. ↩ ↩²

22. Letter from Sen. Richard Blumenthal to CFTC Chair Michael Selig (Apr. 21, 2026), available at https://www.blumenthal.senate.gov/imo/media/doc/20260421_-_cftc_-_market_resolutions_-_finalpdf.pdf. ↩

23. The Block, “Polymarket Says Governance Attack by UMA Whale to Hijack a Bet’s Resolution Is ‘Unprecedented’” (Mar. 2025), available at https://www.theblock.co/post/348171/polymarket-says-governance-attack-by-uma-whale-to-hijack-a-bets-resolution-is-unprecedented; CoinDesk, “Polymarket, UMA Communities Lock Horns After $7M Ukraine Bet Resolves” (Mar. 27, 2025), available at https://www.coindesk.com/markets/2025/03/27/polymarket-uma-communities-lock-horns-after-usd7m-ukraine-bet-resolves. ↩

24. Polymarket US Rulebook (2026.07.02), available at https://polymarketexchange.com/files/legal/Polymarket%20US%20Rulebook%20(2026.07.02).pdf. ↩