Tops

Wintermute, a London-based algorithmic trading firm with more than $3.5 trillion in annual trading volume, said on Friday it is now providing two-sided liquidity on prediction markets, becoming the latest institutional market maker to plug into a sector that has cleared more than $60 billion in trading volume so far in 2026.

The firm is “quoting two-sided markets across event contracts on leading venues,” it said in a blog post, citing more than $20 billion in monthly volume across those venues as of early 2026. A person familiar with the matter told Decrypt the venues include Polymarket and Kalshi, the two largest event-contract platforms.

Wintermute’s role is as a market maker, not a bettor. It is posting continuous bid and offer prices to tighten spreads and absorb large orders, rather than taking directional positions on contract outcomes.

The move puts a top-tier crypto liquidity desk into a category that has graduated from political-betting curiosity into a derivatives-style venue for trading real-world event risk.

Billions in Monthly Volume

Combined monthly global trading volume on Kalshi and Polymarket climbed from less than $5 billion in September 2025 to about $24 billion in April 2026, according to a Pew Research Center analysis of data from The Block. Lifetime trading volume across the two platforms crossed $150 billion in April, with Kalshi posting a record $14.81 billion in monthly notional volume and Polymarket clearing $9.01 billion.

Sports drive the majority of activity on Kalshi — 80% of its volume since July 2024 — while Polymarket’s mix is more varied, with politics at 32% and crypto at 20%, the Pew analysis found.

“Prediction markets have the demand profile of a major asset class but the liquidity profile of an early-stage one,” Jake Ostrovskis, Wintermute’s Head of OTC Trading, said in the company’s statement. “For these markets to become a reliable real-time source of probability estimates, they need sustained two-sided liquidity. That depth tightens spreads, supports larger trade sizes, and in turn improves the signal embedded in market prices.”

Wintermute Is Not First

Wintermute joins Jump Trading and Galaxy Digital, both of which already provide liquidity on event contracts, according to The Block. The arrival of a third top-tier liquidity provider, and one that processes more than $3.5 trillion a year across spot, derivatives and DeFi, signals that professional market makers now see event contracts as a derivatives frontier rather than a side bet.

Same-day regulatory news reinforced the institutionalization arc: the CFTC on Friday cleared Kalshi to offer Bitcoin perpetual futures in the U.S., pushing the platform further into traditional derivatives turf. Defiant has reported separately on Polymarket’s recent Nasdaq Private Market partnership opening event contracts on private-company valuations.

What Could Cool the Sector

Regulatory pressure is mounting in lockstep with the volumes. Spain on May 26 ordered ISP-level blocks on both Polymarket and Kalshi over unlicensed-gambling concerns, the fifth country to move against the platforms in 2026 after Brazil, Indonesia, India and Portugal. In the U.S., a New York Times investigation reported that CFTC officials who raised internal concerns about prediction markets had been suspended and removed from the agency.

The platforms also remain split on regulatory posture. Kalshi is CFTC-regulated and U.S.-only. Polymarket International, the offshore venue that accounts for the bulk of the company’s volume, is not CFTC-regulated; Polymarket US — newly CFTC-approved — cleared $1.3 billion in April 2026 compared with $9 billion at the international venue, per Pew.

For Wintermute, the math still works as long as event-contract volumes keep compounding at the pace of the last eight months. Ostrovskis described the sector as “early-stage” on liquidity — which is the same thing as saying the spreads are still wide enough to make showing up worthwhile.