Judge Allows CFTC Brief Arguing Polymarket Contracts Are Swaps in Van Dyke Insider-Trading Case

Meta description: Judge Margaret Garnett allowed the CFTC to file a brief arguing Polymarket contracts are swaps in Van Dyke’s SDNY case.

Tags: CFTC, Polymarket, Gannon Van Dyke, Southern District of New York, Kalshi, George Santos

Market platform: Polymarket

Category: Regulation

Judge Margaret M. Garnett allowed the Commodity Futures Trading Commission to file an amicus brief in the criminal case against Gannon Ken Van Dyke, the active-duty Army Special Forces soldier accused of making more than $400,000 on Polymarket with nonpublic military information. The August 24, 2026 order in United States v. Van Dyke, No. 1:26-cr-156, gives the agency a formal path to argue that Polymarket event contracts are swaps under the Commodity Exchange Act.

What did the court allow the CFTC to do?

The Southern District of New York granted the CFTC leave to file an amicus brief on August 24, 2026. The agency is not a party to the criminal prosecution, but the order lets it submit its view on a threshold legal issue in the case: whether the event contracts Van Dyke traded on Polymarket fall within the Commodity Exchange Act’s definition of swaps.

That question matters because the indictment’s insider-trading theory depends on the legal character of the contracts. In its proposed amicus brief, the CFTC argues that Polymarket’s event contracts are swaps and that trading them on material nonpublic information can constitute fraud under the Commodity Exchange Act. The defense disputes that framing and has pushed back against the agency’s effort to enter the criminal docket.

Van Dyke’s lawyers, in an August 24 filing in the same case, called the agency “a regulatory wolf” and argued that the CFTC was trying to advance a civil enforcement theory through the criminal proceeding. The court’s order did not decide whether the CFTC’s swaps argument is right. It only allowed the agency to file its brief.

Who is Gannon Van Dyke?

Van Dyke is an active-duty Army Special Forces soldier from North Carolina. Federal prosecutors charged him in the Southern District of New York in a case unsealed on April 23, 2026. According to the CFTC’s April 23, 2026 enforcement release and the federal case materials, Van Dyke traded under the Polymarket handle “Burdensome-Mix” and bought more than 436,000 “Yes” shares on a contract tied to the fate of former Venezuelan President Nicolás Maduro.

The trading took place between December 30, 2025 and January 2, 2026. Prosecutors and the CFTC say Van Dyke used nonpublic information from his military role in an operation targeting Maduro and his wife, Cilia Flores. The CFTC’s April 23 release said the trading generated roughly $404,000 in profit, while the criminal case materials put the figure as high as $409,881.

The factual allegation is unusually direct for the prediction-markets sector: a government employee allegedly used sensitive operational information to trade a real-world event contract before that information was public. The legal question is narrower but consequential for the case. The government must persuade the court that the contracts fit within a statutory framework that supports the charged market-fraud theory.

Why did the defense object to the CFTC brief?

The defense argues that the CFTC is using the criminal case to litigate issues from a parallel civil enforcement action that has been paused. The CFTC brought its own civil case against Van Dyke, and that proceeding was stayed on August 10, 2026, pending the criminal matter. Van Dyke’s August 24 filing says the agency should not be allowed to use amicus status to press the same jurisdictional position in a different forum.

The objection also goes to the substance of the CFTC’s theory. Van Dyke’s lawyers dispute that Polymarket’s contracts are swaps under the Commodity Exchange Act. If the court rejects that view at the motion-to-dismiss stage or later in the case, the ruling would weaken the CFTC’s position in this prosecution. If the court accepts the agency’s reading, the criminal case would proceed with the CFTC’s interpretation in the record.

For now, the procedural point is settled: the CFTC may file. The merits of the swaps argument remain before Judge Garnett, along with Van Dyke’s defense motion to dismiss.

How does this compare with the George Santos Kalshi case?

The Van Dyke case reached the court the same month another insider-trading dispute showed how a regulated prediction-market exchange can discipline users under its own rulebook. Kalshi issued a lifetime ban to former Republican congressman George Santos and imposed a $71,356 penalty after its compliance team found reasonable cause to believe he had traded on inside information.

Santos had traded on a Kalshi market tied to whether he would attend President Trump’s State of the Union address. In its July settlement order, the CFTC said Santos bought contracts that would pay if he did not attend, then sold positions at a profit while publicly signaling that he planned to go to Washington. Santos agreed to pay more than $35,000 and accepted a three-year trading ban from CFTC-regulated platforms, according to the commission’s settlement order.

Kalshi’s lifetime ban went further than the CFTC settlement. The exchange cited Santos’s conduct and said he did not cooperate with its compliance process. Santos responded publicly on X by criticizing Kalshi and calling it a gambling platform.

The Santos and Van Dyke matters are not the same kind of case. Kalshi is a CFTC-regulated exchange, and its action against Santos came through a platform compliance process followed by a CFTC settlement. Polymarket has operated outside the U.S. regulated exchange structure, and the Van Dyke prosecution asks a federal court to apply commodities-law concepts to a Polymarket event contract in a criminal case.

What is at stake in the swaps question?

The immediate issue is whether the criminal case against Van Dyke can proceed on a theory that treats the Polymarket contracts as swaps. The CFTC’s amicus brief gives the court the agency’s formal view that the contracts fall within its statutory jurisdiction and that material nonpublic information can support a Commodity Exchange Act fraud theory in this setting.

That does not turn the Van Dyke case into a general ruling on every prediction market. Any decision will depend on the contracts, facts and statutory arguments before Judge Garnett. Still, the case is being watched because it puts a live federal criminal prosecution next to the unresolved regulatory question at the center of event-contract markets: when does a bet on a real-world outcome become a federally regulated derivatives contract?

The next concrete milestone is Judge Garnett’s handling of Van Dyke’s motion to dismiss and the legal arguments now joined by the CFTC’s amicus brief in United States v. Van Dyke, No. 1:26-cr-156, in the Southern District of New York.