37 attorneys general plus DC signed the brief against Kalshi. Texas did not

On 24 April 2026, thirty-seven state attorneys general and the District of Columbia signed a single brief in Commonwealth of Massachusetts v. KalshiEx LLC, Massachusetts Supreme Judicial Court No. SJC-13906. We downloaded that brief, read it, and copied the names out of its signature block. They are in the table below, all fifty-one jurisdictions, with the thirteen that are not on it. The argument the brief actually makes, and the CFTC releases sitting behind it, are covered on is Kalshi legal.

Texas is not on it. Neither are Florida, Georgia or Washington. That is the single most useful fact on this page, and it is also the one most likely to be misread, so it is worth being exact about what it means: not signing a brief is not the same as saying something is legal. It means that state's attorney general did not join this filing. Nothing more.

Three different questions get answered as though they were one

This is why eleven competitor pages contradict each other on Montana, Illinois, New Jersey, Minnesota and Connecticut. They are not disagreeing about facts. They are answering different questions and labelling all three "legal":

1. Is it lawful for me to trade here? A question about state law.
2. Will the platform let me in? A question about geofencing, which the platform decides and can change on a Tuesday.
3. Am I eligible for the sign-up promo? A question about a marketing offer.

One widely-cited state list is explicitly a promo-eligibility list, and it sits on a page that ranks for a legality query. Another publisher runs a near-identical list as a legality finding. Both can be accurate about their own question and still contradict each other, because they are not answering the same one.

This page answers a fourth question, and only that one: which attorneys general have taken a position on the record. It is the one question with a document behind it.

What the 37 are actually arguing

Kalshi is a CFTC-designated contract market. Nobody in the case disputes that. The argument is about whether federal designation wipes out state gaming law.

The amici say it does not. Their argument runs through 7 U.S.C. section 2(e) of the Commodity Exchange Act, and they lean on the clear-statement rule from Whitman v. American Trucking Associations, 531 U.S. 457, 468 (2001): Congress does not hide fundamental changes in minor provisions. On their reading, if federal designation displaced state sports-betting law, the CFTC would have acquired authority over sports betting nationwide without Congress ever saying so. They point at Murphy v. NCAA, 584 U.S. 453, 486 (2018), for what happens when federal law reaches into that space.

Two of the amici are describing their own licensing regimes: Nev. Rev. Stat. ch. 463 and Ohio Rev. Code ch. 3775. Nevada and Ohio are counsel of record, not just signatories.

Every jurisdiction, and which side of the signature block it is on

Thirty-eight rows say Yes, which is thirty-seven states plus the District of Columbia. That is the brief's own count of itself, and it matches what we read.

The dated record

Every ruling, order and state action in this fight, in date order, with each row saying whether we read the document or a report of it, is on the litigation changelog. Of eleven competitor pages audited for this site, not one carried a changelog or a per-fact verification stamp.

States with their own page

All of them are indexed at Kalshi legality by state, one line each on what actually happened. The longer notes are below.

Two states wrote the brief rather than signing it, and the argument sets out what their law actually requires. Those have pages of their own:

• Is Kalshi legal in Nevada, co-author of the brief, where the licence follows an investigation and insiders are barred from betting on their own sport
• Is Kalshi legal in Ohio, the other co-author, where the voluntary exclusion list puts a duty on the operator
• Is Kalshi legal in Texas, which did not sign, has brought no enforcement action, and whose gambling statute covers election betting on its face
• Is Kalshi legal in Arizona, which brought the first criminal prosecution of a prediction market and was then blocked by a federal court
• Is Kalshi legal in Connecticut, where a federal judge held in August 2026 that the sports contracts are wagers and not swaps
• Is Kalshi legal in Michigan, where a state court ordered the trades unwound and the CFTC then ordered them honoured
• Is Kalshi legal in California, where the enforcement attempt came from three tribes and a federal judge refused it
• Is Kalshi legal in New Jersey, where the Third Circuit affirmed an injunction for Kalshi on 6 April 2026
• Is Kalshi legal in New York, where the state sued the exchange after the exchange sued the state and lost
• Is Kalshi legal in Massachusetts, which is not a signatory because it is the plaintiff everyone signed behind
• Is Kalshi legal in Tennessee, which lost an injunction in February 2026 and signed the brief in April anyway
• Is Kalshi legal in Maryland, where the preemption argument first failed at the trial level in August 2025
• Is Kalshi legal in Illinois, which taxed prediction markets and demanded a $15 million sports betting licence
• Is Kalshi legal in Rhode Island, where both sides sued each other on the same afternoon

Those fourteen are the states where a document exists to write from. The other thirty-seven do not have pages, deliberately: a page holding only an attorney general's name is the thing this site exists to beat.

They do not agree with each other, and that is the finding. Read in date order, the same question has been answered both ways by federal courts:

The Third Circuit, a federal court of appeals, held that sports event contracts “are swaps traded on a CFTC-licensed DCM, so the CFTC has exclusive jurisdiction”. Four months later a federal district judge in Connecticut held they fail the statutory definition of a swap, because the result of an event is not the occurrence of an event. Both were reading 7 U.S.C. Anyone giving you a single national answer today is picking one of those rows and omitting the rest.

The federal regulator is suing states as well

This is the part that gets left out of state-by-state lists entirely. The states are not only arguing with the exchange; the Commodity Futures Trading Commission has brought its own actions against states to assert exclusive jurisdiction. Reporting we read names nine: Arizona, Connecticut, Illinois, New York, New Mexico, Minnesota, Rhode Island, Wisconsin and Kentucky.

Five of those nine, Wisconsin, Montana, New Mexico, Minnesota and Kentucky, do not have pages here. That is deliberate. For each we could establish that something happened and almost nothing about what, and a page carrying one sentence and a state name is the thing this cluster exists to beat. When there is a document to read, they get pages.

What the nine tell you in the meantime: in Arizona it was the federal government's motion, not Kalshi's, that produced the injunction against the state, and in Michigan the Commission directed the exchange to honour trades a state court had ordered unwound. The dispute is not simply platform against state.

The thirteen that are not on the brief

Florida, Georgia, Indiana, Kentucky, Massachusetts, Missouri, Montana, New Hampshire, North Dakota, Texas, Washington, West Virginia and Wyoming.

Massachusetts belongs in that list for a different reason from the other twelve: it is the party bringing the case. It did not sign an amicus brief because it is the appellee. Reading Massachusetts as neutral would be exactly backwards.

For Texas we now know part of the answer, and it is not disagreement on the record. According to Texas Tribune reporting we read, the National Association of Attorneys General and the Ohio attorney general's office asked Texas in March 2026 to join an earlier brief making the same argument. Thirty-nine states signed. Attorney General Ken Paxton's office did not respond. The two organisations asked again for this brief, and again there was no response. Asked whether Texas gambling law applies to prediction markets, the office declined to comment and declined to release internal communications, citing attorney-client privilege. Being asked twice and not answering is a different fact from disagreeing, and it is the one on the record.

For the other eleven we do not know. An attorney general may decline to join a multistate brief because they disagree, because the office was mid-transition, because of a scheduling problem, or because they are pursuing their own route. The brief does not say, and we did not find a document that does.

Absence of a signature is not a finding of legality. That is the exact defect running through the competitor pages: one of them headlines that Kalshi is legal in Texas as of July 2026, and its own body text says only that no known Texas state-level action is blocking it. Nothing known is a statement about the state of our knowledge. It is not a statement about the law.

Federal regulation is real, and it does not settle this

Three CFTC actions on event contracts sit in the background, both read direct from cftc.gov: Release 9273-26 of 24 July 2026, a Division of Market Oversight advisory on self-certification of an event contract series, and Release 9282-26 of 12 August 2026, a DMO advisory on self-certification of incentive programs.

Those are real, and they are about federal process. They do not resolve the question in SJC-13906. Anyone citing CFTC designation as though it ends the argument is skipping the argument.

What we could not verify

The site's position is being the one that says this out loud.

• The state court dockets. We have the SJC number and the Appeals Court number from the brief itself. We did not pull the Suffolk Superior Court docket, the Nevada docket or the Ohio docket. Every date attached to those proceedings on the parent page is labelled as secondary reporting, and none of it is repeated in the table above.
• Geofencing, per state, per platform. We have not tested which states either platform blocks. The table above deliberately has no column for it, because we would be guessing.
• Promo eligibility. Same reason. It is a marketing setting, it changes without notice, and it is not a legal fact.
• Why twelve states did not sign. No document found.
• Anything after 20 August 2026. This page is a reading of one filing from 24 April 2026 and two CFTC releases. Litigation moves. If you are reading this much later, the signature block has not changed, but the case may have.

Questions people actually type

Is Kalshi legal in Texas? Texas is one of thirteen jurisdictions not on the 37-state amicus brief in SJC-13906. That is all we can tell you from a primary document. It is not a finding that trading is lawful there, and we did not locate a Texas statute, order or docket either way. Pages that say Texas is settled are usually reporting that nothing is known.

Is Kalshi legal in California? California signed. Attorney General Rob Bonta is on the signature block of the brief supporting Massachusetts, one of the 37 states plus DC. That tells you the position California's attorney general has taken on the record. It does not by itself tell you whether the platform is open to you today.

Is Polymarket legal in the USA? This page does not answer that, and no honest page answers it in one line. The brief we read is about Kalshi, in one Massachusetts case. Polymarket's US access question runs through a separate structure, covered on its own page. Anyone answering for both platforms from one document is overreaching.

How many states are against Kalshi? Thirty-seven states plus the District of Columbia signed the amicus brief, which is 38 jurisdictions, and Massachusetts is separately the party bringing the case. That is 38 attorneys general on one side of one filing. It is a count of signatures on a brief, not a count of states where trading is prohibited.

Does the CFTC make Kalshi legal everywhere? Kalshi is a CFTC-designated contract market and that designation is real. The 37 amici argue it does not displace state gaming law, running through 7 U.S.C. section 2(e) and the clear-statement rule in Whitman, 531 U.S. 457, 468 (2001). That argument is live at the SJC. Treating federal designation as the end of the question skips the case.

Why do other sites disagree about my state? Because most of them are publishing a promo-eligibility list under a legality headline. Of eleven competitor pages audited, not one cited a case name, docket number, statute section or CFTC order. They contradict each other on at least five states: Montana, Illinois, New Jersey, Minnesota and Connecticut.

What this page is not

It is not legal advice, and we are not lawyers. It is a reading of one public filing, with the filing linked so you can check the signature block yourself. If your question is whether you personally may trade, that is a question for someone licensed to answer it in your state.