New Jersey's SCOTUS Petition Changes Everything for Kalshi

New Jersey's Supreme Court petition — filed September 2, 2026, the same week the Ninth Circuit handed states their first major appellate win — marks the moment a messy, multi-front regulatory battle crystallised into a single, binary question that only nine justices can settle. Combined Kalshi/Polymarket trading hit $45.33 billion in August before pulling back 14.5% — and sports event contracts, the legal flashpoint, account for roughly 80% of Kalshi's entire revenue base. The court's decision to grant or deny certiorari will either validate a $22 billion company's core business model or force a structural rethink of the entire prediction-market industry.

---

The Week That Made SCOTUS Inevitable

Prediction markets have spent 18 months accumulating legal kindling. This week, someone lit a match.

New Jersey Attorney General Jennifer Davenport filed a petition with the Supreme Court on Wednesday, asking the justices to determine whether prediction market company Kalshi can offer sports contracts despite state gambling laws.

The timing was not incidental.

Davenport filed for cert shortly after the Ninth Circuit's ruling against prediction markets created a federal court split with the April decision from the Third Circuit that allowed Kalshi and competitors to offer sports event contracts in New Jersey.

That split is the operative fact of the week. Two federal circuit courts, examining essentially the same statutory question — does the Dodd-Frank Act's treatment of "swaps" preempt state gaming laws when contracts trade on a CFTC-registered exchange? — reached diametrically opposite conclusions within five months of each other. That is the textbook condition for Supreme Court review.

The split between the rulings from the Third and Ninth Circuit courts provided an opportunity for the Supreme Court to get involved and review which regulator should have oversight of prediction markets, Bank of America said in a Monday note.

Critically,

a CFTC spokesman said the split called for "resolution by the Supreme Court."

When the regulator ostensibly on one side of the argument publicly invites the court to intervene, the question has left the realm of regulatory skirmishing and entered constitutional law.

---

The Two Rulings and What They Actually Said

The circuit split is not cosmetic — the two courts applied genuinely different statutory interpretations, and that matters for predicting how SCOTUS might frame the issue.

In a 2-1 opinion on April 6, 2026, the Third Circuit became the first federal appellate court to hold that the Commodity Exchange Act preempts state gambling laws as applied to sports-related event contracts traded on CFTC-registered designated contract markets.

The majority reasoned that the CEA's definition of "swap" — broad enough to capture any contract whose payout depends on the occurrence of a contingent event — encompasses Kalshi's yes/no sports positions.

The Ninth Circuit, ruling on August 28, arrived at the opposite conclusion using the same statutory text.

On August 28, the Ninth Circuit ruled that the Commodity Exchange Act likely did not preempt Nevada's gaming regulations as applied to Kalshi's sports contracts, therefore allowing Nevada to enforce its gaming laws against the company's sports-related contracts — creating a direct conflict with the earlier Third Circuit ruling.

The Ninth Circuit's conceptual anchor:

"Congress has spoken on the issue of gambling in other statutes and did not impliedly repeal or amend those statutes through Dodd-Frank… adopting that reading would assume that, by granting the CFTC regulatory authority over gaming nationwide, Congress 'hid an elephant in a mousehole.'"

That phrase — "elephant in a mousehole" — is borrowed directly from major questions doctrine jurisprudence, a signal that the Ninth Circuit was deliberately writing for a higher-court audience.

The particular issue is whether Congress in enacting the 2010 Dodd-Frank Wall Street Reform and Consumer Protection Act intended to federalize a multi-billion-dollar sports-wagering industry.

It did not say so explicitly. That silence is where the entire legal fight lives.

---

The Business Reality Underneath the Legal Theory

Abstract statutory interpretation arguments move slowly through courts. The business pressures do not.

Sports accounted for 95% of Kalshi's revenue last year, according to New Jersey's filing.

That figure reframes the entire litigation: this is not a peripheral product line under threat; it is the company.

As of February 2026, roughly 87% of Kalshi's $39.7 billion traded in the past year was on sports.

Kalshi did not stumble into sports by accident.

With a change in leadership in January 2025, the CFTC changed its stance toward event contracts, signalled by then-Acting Chair Caroline Pham's February 2025 press release stating that "current Commission interpretations regarding event contracts are a sinkhole of legal uncertainty," and Kalshi and other prediction markets began offering sports-related markets in January 2025.

The growth that followed was rapid.

According to Pew Research Center, the combined monthly trading volume on Kalshi and Polymarket more than quadrupled in a span of eight months, from less than $5 billion in September 2025 to $24 billion in April 2026.

By July, the World Cup pushed the industry to a new peak before a post-tournament hangover:

combined trading volume across Kalshi, Polymarket and Polymarket US fell 14.5% in August from the previous month to $45.33 billion, with Kalshi generating $37.17 billion in August volume and Polymarket recording a combined $8.16 billion — a 36.7% decline from $12.89 billion a month earlier.

Both prediction markets are gearing up for the NFL football season that kicks off on September 9 and is expected to attract substantial contract activity from sports fans.

That means the industry enters its highest-revenue period of the year with maximum legal uncertainty — a combination that concentrates operator risk in precisely the moment it can least afford it.

The top contracts on the order book right now illustrate the commercial stakes directly: MLB matchups — the Dodgers vs. Braves ($7.36M), Rockies vs. Nationals ($5.37M), Diamondbacks vs. Giants ($3.41M) — are generating eight-figure single-game volumes. These are not niche markets. They are the product category at the center of the Supreme Court petition.

---

The Plaintiff Coalition: States, Tribes, and Traditional Operators

One analytically underweighted dimension of this week's news: the NJ petition did not arrive in isolation. It caps a coordinated, multi-front campaign that has drawn in actors with very different motivations but a shared short-term interest in restraining Kalshi.

Currently, some 80 cases are filed in state and federal courts, with about 85% of the decisions going against prediction markets, according to Joe Webster, a partner with Hobbs Strauss.

State governments represent the most visible front:

at least 12 states are now in active legal conflict with Kalshi or Polymarket — either through lawsuits, cease-and-desist orders, or extended bans — and the number is growing.

New York sued Kalshi for $36 billion on July 31, 2026.

That number — calculated as the total allegedly untaxed sports-related contract volume routed through the platform since launch — is not a realistic damages claim so much as a political statement about the fiscal stakes.

The American Gaming Association's CEO Bill Miller estimated that "prediction market evasions of state and tribal law have siphoned more than $1.2 billion in gaming tax revenue from critical community initiatives across America."

Tribal governments bring a separate legal theory.

Tribal governments in both California and Wisconsin sued Kalshi in federal court, alleging Kalshi's sports event contracts violate the Indian Gaming Regulatory Act, tribal-state compacts, and federal advertising laws.

Four New Mexico tribes and pueblos on May 12, 2026, sued the prediction market platform Kalshi, alleging the app's operation in New Mexico violates tribal sovereignty and state law.

The IGRA theory has so far failed at the district court level —

courts concluded that Kalshi's internet-based event contracts are governed by the Commodity Exchange Act and the Unlawful Internet Gambling Enforcement Act, rather than IGRA, and that questions fall within the CFTC's exclusive jurisdiction

— but tribal appeals are pending in the Ninth Circuit.

Traditional sportsbooks — DraftKings, FanDuel, Flutter — are funding and supporting state advocacy without always appearing on pleadings directly.

DraftKings, Fanatics, FanDuel, Underdog Fantasy, and PrizePicks all routed at least some of the bets placed in their apps through exchanges they do not own.

The incumbents' ambivalence is notable: they oppose Kalshi's unlicensed model, but several are simultaneously building their own event-contract infrastructure in case the Supreme Court rules for Kalshi.

---

What the CFTC's Position Actually Means

The CFTC's institutional posture is the most underappreciated variable in this dispute. Federal agencies do not typically sue sister-state governments. The CFTC has done exactly that.

The CFTC actively supports prediction markets, suing states that attempt to regulate them, while 44 state attorneys general contend the CFTC exceeds its authority.

The CFTC under Chairman Mike Selig has chosen a side and armed it.

That posture is a product of deliberate policy, not statutory ambiguity alone.

In 2025, the CFTC dropped its appeal of the Kalshi litigation; in 2026, it withdrew a 2024 proposed rule

that would have constrained event contracts. Each of those moves was a structural concession to the prediction-market industry.

More than 34 states, the District of Columbia and Northern Mariana Islands filed amicus briefs asserting state regulatory authority — a level of opposition that may independently attract the Supreme Court's attention even absent a formal split.

The CFTC's willingness to litigate against that coalition signals it views the stakes as existential for its own jurisdictional footprint. A Supreme Court ruling that state gaming laws can coexist with CFTC registration would materially constrain the agency's authority over a product category it has claimed exclusively.

---

The Counter-Argument

The strongest case for Kalshi — and for the Third Circuit majority — deserves honest engagement rather than dismissal.

The CEA's definition of "swap" is genuinely, textually broad. Congress in 2010 wrote language designed to capture novel financial products precisely because legislators knew they could not enumerate every future instrument. Kalshi's yes/no sports positions share structural features with binary options and variance swaps: they pay a fixed amount on occurrence of a defined event, they are marked to market, and they carry counterparty risk intermediated through a clearinghouse. The Third Circuit did not invent this reading; it followed the statutory text where it led.

Kalshi maintains that the CFTC's exclusive jurisdiction over its registered exchange overrides state gambling laws

— and that argument carries constitutional weight. The Supremacy Clause is not merely a tiebreaker; it is a structural principle. If Congress granted the CFTC exclusive authority over all swap transactions on registered exchanges, that grant does not evaporate because individual states disagree with the policy outcome.

The major-questions framing the Ninth Circuit applied is itself contested. The doctrine — that courts should not attribute vast regulatory power to agencies absent clear congressional statement — was developed to constrain agency rulemaking, not to limit what a registered private exchange may do. Kalshi is not an agency asserting new authority; it is a private company operating under an existing registration regime. That distinction matters, and a textualist Supreme Court majority may find it dispositive.

Prediction market traders currently assign a 64 percent probability that the Supreme Court will accept a sports event contract case by the end of 2026.

Acceptance does not predict outcome — but it does indicate the community most financially exposed to this question sees the federal argument as viable, not merely a litigation tactic.

---

The Dodd-Frank "Elephant in a Mousehole" — and Why It Might Not Hold

The Ninth Circuit's "elephant in a mousehole" framing is rhetorically compelling but analytically incomplete. The doctrine, articulated in Whitman v. American Trucking and popularised by Justice Scalia, addresses hidden regulatory elephants — enormous claimed powers with no visible congressional footprint. But the CEA's swap definition is not hidden. It is definitional, explicit, and was debated extensively in 2010 conference reports. Congress knew it was writing broad language.

The Ninth Circuit held that sports event contracts are not "swaps" under federal commodities law, directly conflicting with the Third Circuit's reasoning and creating a circuit split.

That conflict means at least one circuit is wrong about basic statutory interpretation. The Supreme Court's task is to determine which one — and the answer will turn on how the justices read the interaction between the CEA swap definition, the Dodd-Frank preemption clause, and the pre-existing gaming carve-outs in other federal statutes.

The gaming carve-out argument is states' strongest specific textual hook:

the petition argues Congress did not clearly authorize federally registered markets to offer sports betting across the country without complying with state gambling laws.

The Wire Act, PASPA's history, and PASPA's repeal via Murphy v. NCAA (2018) all suggest Congress understood sports wagering as a state-regulatory domain. If the Court reads Dodd-Frank against that backdrop, Kalshi's position becomes harder to sustain.

---

The NFL Season as a Real-Time Legal Stress Test

The NFL calendar creates a peculiar temporal urgency here.

Both prediction markets are gearing up for the NFL football season that kicks off on September 9 and is expected to attract substantial contract activity from sports fans.

Prior NFL seasons produced the industry's peak weekly volumes; the September–February window is when sports event contract revenue accretes fastest.

Kalshi enters this season operating legally in some states (under Third Circuit protection), under injunction in others (Massachusetts, New York), and in a regulatory grey zone in most of the remaining 38 states where cases remain unresolved.

State regulators in Nevada, Massachusetts, and Tennessee pressed forward with enforcement actions against Kalshi, with divergent outcomes in federal and state courts.

This patchwork creates genuine compliance complexity for Kalshi but also generates the evidentiary record the Supreme Court will eventually review. Every week the NFL runs on Kalshi's platform with multi-million-dollar daily volumes in contested states is a week of facts that will appear in certiorari briefs.

Kalshi recently reached a multi-year agreement with the U.S. Tennis Association to become the US Open's exclusive prediction-market partner, with the partnership beginning with the 2026 tournament's singles main draw on August 30.

Signing official league partnerships mid-litigation is not coincidental strategy; it is reputation management designed to normalise the product while courts deliberate.

The market data from this week's top contracts reinforces the scale argument: more than $16 million across three single MLB matchups in the opening widget above. At NFL-season velocity, weekly sports contract volumes will dwarf those figures. The Supreme Court may be asked to hear this case while those numbers are still climbing.

---

What I'm Watching

1. Kalshi's opposition brief — due within 30 days of September 2.

New Jersey's petition for cert triggers a set of required steps that will play out over the next two months: an opposition brief from Kalshi is due within 30 days.

Watch the brief for whether Kalshi attempts to reframe the question presented — narrowing it to avoid major-questions doctrine — or goes full textualist. The framing choice signals litigation confidence.

2. The 9th Circuit tribal appeal — decision expected by year-end.

The tribes appealed the Northern District of California's denial of injunctive relief to the Ninth Circuit, which heard argument on the tribes' appeal on July 12, 2026.

A tribal-sovereignty holding against Kalshi from the Ninth Circuit would add an Indian Gaming Regulatory Act dimension to the SCOTUS petition, potentially broadening the cert question and complicating Kalshi's position further.

3. NFL Week 1 volume on Kalshi — September 7–8. The opening weekend's contract volumes in states under active enforcement litigation (New York, Massachusetts) will indicate whether users are self-selecting out or whether Kalshi is actively geofencing. That compliance behaviour will feature prominently in state briefs.

4. Connecticut's active litigation and whether the CFTC files amicus.

Connecticut sued Kalshi last week seeking to stop the company from offering sports contracts, extending a legal dispute between the state and the prediction-market operator.

If the CFTC files a federal amicus in the Connecticut matter before the certiorari question is settled, it will signal the agency is prepared to litigate all the way to conference — a meaningful escalation indicator.

5. Congressional action — Senate Commerce Committee hearing, fall 2026 schedule.

Wake Forest economist Koleman Strumpf's read: "It's going to be something the Supreme Court, and maybe even Congress, will have to weigh in on."

Watch for Senate Commerce or House Financial Services scheduling hearings on prediction market regulation this fall. Congressional hearings are often a leading indicator of legislative intent that SCOTUS justices may cite in oral argument to assess what Congress "clearly" authorised in 2010.

---

All volume and legal data sourced from The Block, Pew Research Center, court filings, and primary reporting cited inline. Positions in prediction market event contracts carry material financial risk; legal outcomes are binary and unresolved. This analysis does not constitute legal or financial advice.