UK Betting Heavyweights Surge as US Bill Targets Prediction Markets' Sports Wagers

On March 23, 2026, shares of major UK-listed gambling companies spiked dramatically on the London Stock Exchange, a direct response to bipartisan legislation introduced in the US Senate by Adam Schiff, a California Democrat, and John Curtis, a Utah Republican; the bill seeks to bar CFTC-regulated prediction market platforms such as Kalshi and Polymarket from offering sports betting contracts, thereby shielding established sportsbooks from upstart competition.

Flutter Entertainment, the Irish powerhouse behind FanDuel—the leading US sports betting app—saw its shares climb 7.6% that day, while Entain, the British firm that owns Ladbrokes and co-operates BetMGM, posted a 6.4% gain; investors clearly viewed the proposed law as a win for traditional operators who hold state-issued gambling licenses across numerous US jurisdictions.

Trading volumes surged alongside the prices, with Flutter's stock drawing heightened attention from institutional buyers who bet on regulatory tailwinds favoring incumbents; Entain followed suit, its rise reflecting similar optimism about reduced competitive pressures from unregulated alternatives.

What's interesting here is how quickly the market digested the news—within hours of the bill's announcement, share prices reflected expectations of a leveled playing field, where licensed sportsbooks could reclaim market share lost to prediction markets operating under looser federal oversight.

Senators Schiff and Curtis framed their proposal as a measure to close a regulatory loophole, arguing that platforms overseen by the Commodity Futures Trading Commission (CFTC) have encroached on sports betting—a domain traditionally reserved for state-licensed entities—without adhering to the same consumer protections or tax obligations.

The bill specifically prohibits these prediction markets from listing event contracts tied to sports outcomes, such as NFL game winners or NBA point spreads; proponents highlight that such contracts mimic binary options on athletic events, blurring lines with straight wagers while evading state-level gambling laws.

According to reports, Kalshi alone channeled about 90% of its trading volume into sports-related contracts by early 2026, a figure that underscores the scale of disruption to conventional sportsbooks; Polymarket, known for election and crypto bets, has similarly expanded into athletics, drawing users with lower barriers to entry and innovative contract designs.

Prediction markets operate by letting users trade shares in yes/no outcomes for real-world events, a model approved by the CFTC for certain non-gambling uses but increasingly applied to sports; unlike traditional bets settled by bookmakers, these platforms match buyers and sellers directly, often resulting in tighter odds and higher liquidity for popular events.

Kalshi reported sports betting volumes eclipsing all other categories combined, a trend that caught regulators' eyes since these trades bypass state gambling commissions entirely; Polymarket, while crypto-based, has mirrored this growth, attracting bettors frustrated by geoblocking or high vig on apps like FanDuel or DraftKings.

Turns out, this competition has squeezed revenues for licensed operators, who invest heavily in compliance, marketing, and partnerships with leagues like the NFL or NBA; data from industry trackers shows prediction platforms capturing slices of the $10 billion-plus monthly US sports handle, particularly in states with nascent legal betting markets.

Flutter Entertainment dominates the US landscape through FanDuel, which commands over 40% market share in online sports betting according to recent American Gaming Association figures; the company, listed on both London and New York exchanges, reported robust 2025 growth fueled by expansions into new states, yet faced headwinds from prediction market inroads.

Entain, meanwhile, leverages its BetMGM joint venture with MGM Resorts to compete fiercely, blending UK roots with American scale; Ladbrokes provides a steady domestic base, but US exposure via BetMGM has driven recent volatility, with the March 23 surge signaling relief from federal intervention.

Both firms have lobbied extensively for clearer boundaries between gambling and derivatives trading, aligning with sports leagues that fear dilution of official betting partnerships; observers note that the bill's introduction timed perfectly with mounting CFTC scrutiny of Kalshi's sports offerings, amplifying its market impact.

The CFTC's role in prediction markets stems from the 2020 Commodity End-User Clarification Act, which greenlit event contracts excluding gaming-like activities; yet court battles, such as Kalshi's 2024 win allowing election bets, have emboldened platforms to test sports boundaries, prompting congressional pushback.

Senator Schiff, long vocal on financial consumer protections, partnered with Curtis—a tech-friendly conservative—to craft bipartisan appeal, a rarity in polarized Washington; the bill now heads to committee, where amendments could refine its scope, but early endorsements from gaming trade groups suggest momentum.

And while UK stocks reacted first, ripples extended to US-traded peers like DraftKings, whose shares edged up 2-3% amid speculation of industry-wide gains; that's where the rubber meets the road for global operators intertwined with American markets.

If enacted, the legislation would force Kalshi and Polymarket to delist sports contracts, redirecting bettors back to state-regulated apps; figures indicate traditional sportsbooks already process over 90% of US wagers, so even modest shifts could boost handles by hundreds of millions monthly.

People who've tracked this space point to Australia's experience, where the Australian Communications and Media Authority cracked down on unlicensed offshore betting, yielding measurable upticks for local licensed books; similar patterns emerged in Canada post-2021 legalization, underscoring the bill's potential ripple effects.

Flutter's FanDuel boasts integrations with leagues for official data feeds, a moat prediction markets lack; Entain's BetMGM emphasizes responsible gaming tools mandated by states, contrasting with federal-only oversight on CFTC platforms.

One study from a university gaming research center revealed that 15-20% of casual sports bettors experimented with prediction apps in 2025, often citing better pricing; curbing that flow could stabilize yields for incumbents grappling with promotional spending wars.

As the bill advances, stakeholders monitor CFTC responses and potential lawsuits from affected platforms; Kalshi has vowed to fight similar restrictions before, winning key rulings that expanded its footprint.

Yet with bipartisan sponsorship and industry backing, passage seems plausible by mid-2026, especially if tied to broader derivatives reform; for UK-listed giants like Flutter and Entain, the March 23 surge marks an early victory lap, one that underscores how transatlantic regulations shape betting fortunes.

The introduction of this US Senate bill on March 23, 2026, catalyzed a sharp rally in UK gambling stocks, highlighting tensions between innovation and incumbency in the evolving sports wagering arena; Flutter's 7.6% leap and Entain's 6.4% climb reflect investor bets on protected turf, as prediction markets like Kalshi—90% sports-driven—face curbs for lacking state licenses. Data and precedents suggest traditional operators stand to regain ground, reshaping a market where federal rules now collide with state regimes.