Polymarket has self-certified a new class of sports event contracts with the Commodity Futures Trading Commission (CFTC) that would bring parlay-style trading to its regulated U.S. prediction market exchange.
The May 20 filing by Polymarket’s QCX LLC uses both “combinatorial” and “combinatoric” language to describe the multi-leg sports contracts. The cover letter describes the product as a “Combinatorial Outcome Contract,” while the public terms in the filings call it a “Combinatoric Athletic Outcome Contract,” or CAOC. The template question is: “Will {outcomes} occur in athletic {events}?”
Polymarket told the CFTC it intends to list the products no earlier than May 21.
The filing does not use the word “parlay,” but the mechanics closely resemble the sportsbook product. The contracts would combine two or more underlying sports event contracts into a single position, with each underlying event treated as a leg. The combined contract pays out only if every selected leg resolves in the trader’s favor.
The Polymarket US filing does not specify what the user-facing product will look like. It says versions of the contracts will be issued “on an as-needed basis at the discretion of the Exchange,” leaving open whether Polymarket US plans to launch a custom combo builder, pre-built combinations or some mix of both. Given the structure, though, the filing appears designed to support repeatable parlay-style sports markets rather than one-off novelty contracts.
Multi-leg markets become a competitive focus
Polymarket US would be entering a category that has quickly become a priority for sports-focused prediction market operators.
Kalshi launched “combos” for all users in mid-December, months after self-certifying a similar contract structure with the CFTC. In a Dec. 15 LinkedIn post, Kalshi CEO Tarek Mansour said combos were “officially live for everyone on Kalshi” and had generated more than $100 million in volume the prior week. Mansour framed the product as a way to get better prices on multi-leg trades, saying combos let traders bundle positions while other traders compete in the open market to take the other side.
The product has since become a meaningful part of Kalshi’s sports business. In late April, Kalshi’s exotics category, which includes combo markets that function like parlays, hit a record $412.5 million in weekly volume. That represented 10.6% of Kalshi’s total volume, enough to make them the platform’s second-largest category.
DraftKings Predictions has also expanded into parlays. SBC Americas reported earlier this month that DraftKings launched a Combos product that lets users combine multiple sports event contracts into one trade. A company spokesperson told SBC the feature is available across DraftKings Predictions’ sports markets, with up to six event contracts allowed in a single combo.
FanDuel Predicts is likewise leaning into combos. FanDuel parent company Flutter said in its Q1 earnings release that it began testing market-making services in April on a major third-party prediction market platform, and executives tied that work directly to prediction-market parlay or “combo” trades. Flutter CEO Peter Jackson said market making gives FanDuel a way to monetize its pricing expertise, especially around combos, while the company continues building out FanDuel Predicts.
Crypto.com-linked platforms are also adding parlay-style products. The company’s OG.com has a public parlay page for sports event contracts. Fanatics Markets, which launched through a Crypto.com partnership, also describes combo pricing through a request-for-quote (RFQ) process, where a combo order is sent to the exchange and liquidity providers can respond with “executable price quotations.”
Why parlays matter
The product race is not happening by accident. Parlays are one of the most popular and lucrative products in U.S. sports betting because they offer users the chance at larger payouts but are more difficult for users to win.
A Washington Post analysis found that parlays often account for a much larger share of sportsbook revenue than handle. In Maryland, bettors spent 36% of their sports betting dollars on parlays this year, but those bets generated 67% of sportsbook revenue. The Post also cited a Rutgers analysis of New Jersey betting data showing bettors lost $1.41 for every dollar won on parlays, compared with $1.16 on point spreads and $1.10 on over/unders.
Prediction market exchanges do not have the same economics as sportsbooks. Kalshi, Polymarket US and other exchange-based platforms generally match traders against each other rather than acting as the house. That means combo-style contracts wouldn’t create the same operator “hold” that sportsbooks get from parlays.
But the appeal is similar on the user side. Multi-leg contracts can turn a small position into a larger potential payout, while giving sports-focused platforms a familiar product format that many bettors already understand.
Polymarket US filing puts focus on regulated platform
The filing applies to Polymarket US, the company’s CFTC-regulated exchange, rather than Polymarket’s international platform.
A “Parlays” page on Polymarket’s global site shows some pre-built parlay-style markets, including “NBA: SGA Award Parlay,” which depends on Shai Gilgeous-Alexander winning league MVP and Finals MVP honors while Oklahoma City wins the championship. Other examples include an Elon Musk market tied to whether a series of milestones occur by the end of 2026, and a services outage market tied to whether multiple major internet platforms will go down at the same time.
Those markets are pre-built yes-or-no contracts that depend on multiple outcomes, not a sportsbook-style parlay builder that lets users combine separate markets into their own custom trade.
The Polymarket US filing could point in that direction. It does not say whether users will be able to build their own combos like they can on Kalshi, but it lays out a structure for multi-leg sports contracts that can be listed repeatedly on the exchange. If Polymarket builds that functionality for its U.S. platform, it could later apply a similar product experience to its international platform.
The bigger takeaway is that U.S. prediction market platforms are increasingly offering sportsbook-like features while they fight state regulators over whether sports event contracts are federally regulated financial products or unsanctioned sports betting. Parlays are one of the clearest examples of that overlap.
