Cantor Fitzgerald has opened an institutional block desk for prediction markets, and the revealing detail is what the bank did not have to build. Kalshi’s block trading rulebook was already live — a 25,000-contract minimum, Eligible Contract Participants (ECPs) only, all listed markets eligible — and was last updated on May 20, 2026. The plumbing existed. What was missing was a broker institutions already have paper with, and someone willing to quote the other side in size.
Cantor Fitzgerald & Co. said on August 19, 2026 that it is acting as an introducing broker for institutional-size block trades in event contracts on Kalshi, the CFTC-regulated designated contract market, with Susquehanna Predictions supplying pricing and liquidity. The desk sits in Cantor’s Global Markets division under co-chief executives Pascal Bandelier and Christian Wall, and the bank has signalled that more venues will follow Kalshi. It is among the first full-service investment banks to put event contracts on an institutional execution ticket.
What an introducing broker does — and does not — do
The introducing-broker label matters more than the headline. An introducing broker arranges the trade; it does not carry the position, hold customer margin, or clear. Kalshi’s block report must name the contract, price, quantity, execution time and the clearing members involved — so someone else stands between Cantor’s clients and the clearing house.
That gap is the announcement’s biggest unanswered question. Clear Street became the first institutional futures commission merchant (FCM) on Kalshi’s exchange and clearing house on May 1, 2026, citing block trading and swap structures for exchange-traded fund (ETF) issuers. Neither Cantor nor Kalshi has said which FCM carries the new flow, or what initial margin an event-contract block attracts. For a buy-side desk sizing a first trade, that is the operative detail.
The mechanics, and the benchmark problem
Under Kalshi’s framework, a block is negotiated bilaterally at a single price away from the central order book, reported within 15 minutes and published separately from ordinary transactions. Separate orders cannot be aggregated to reach the 25,000-contract floor, and both sides must qualify as ECPs under the Commodity Exchange Act. Traders will recognise the architecture: the same off-book, report-it-afterwards logic that worked cleanly when CME scaled its own block regime.
The transplant is imperfect. Kalshi requires a block price to be “fair and reasonable” given size and available market data — but event contracts have no consolidated tape and no national best bid and offer. On a binary contract, “available market data” may be a handful of resting orders. Price improvement is easy to claim and hard to measure, and compliance teams will press that first.
Who else is moving
Susquehanna is not a neutral utility here. Its predictions unit is the most active liquidity provider in event contracts, so the firm most likely to take the other side is also the pricing partner to the bank bringing the buyers. A legitimate market-making structure — and a disclosure question worth asking.
Rivals are not standing still. CNBC reported on June 2, 2026 that Polymarket completed its first block trade, a six-figure transaction. Interactive Brokers on May 14, 2026 unified Kalshi, CME Group and its ForecastEx contracts into one interface, per Finance Magnates, which also reported the SEC deferring roughly two dozen prediction-market ETF filings. Distribution keeps arriving faster than the wrappers. CME has listed event contracts on Bitcoin futures since 2023; retail access came earlier via FOREX.com and Webull.
“Prediction markets are growing rapidly, but institutional participation has not kept pace because investors have lacked the ability to transact at scale on a regulated exchange,” said Pascal Bandelier, co-chief executive and global head of equities at Cantor Fitzgerald, in comments carried by PYMNTS. Joe Grubb, head of business development at Susquehanna Predictions, called “large institutional risk transfer” the next area of material growth. Max Crowley, vice president of business development at Kalshi, said Cantor “brings deep institutional relationships and significant experience executing in equities and fixed income markets.”
Why the timing works
The demand data was already there. Kalshi raised $1 billion at a $22 billion valuation on May 7, 2026, led by Coatue, disclosing that annualised volume tripled from $52 billion to $178 billion in six months while institutional volume rose 800%. Read together, the “institutions are absent” framing looks strained: institutions were already the fastest-growing slice of the book before any bank arrived. Cantor is not creating that demand — it is intermediating flow that was coming anyway, on terms a fund’s execution policy can approve.
Crypto ran the identical sequence — retail venue, market maker, prime broker and FCM, bank-intermediated blocks, then the ETF fight — so the next constraint is predictable. Not access: clearing capacity, margin treatment and the wrapper. Kalshi chief executive Tarek Mansour has said event contracts “could become a trillion-dollar market.” Until an FCM is named, margin schedules published and a workable reference price exists for off-book prints, institutional size will arrive in increments. Expect a second bank within two quarters — and expect the state-level challenges Kalshi has been contesting to shape which clients may participate long before liquidity does.
Rick Steves
Rick Steves has seen business and economics through many lenses. He joined the financial services industry in 2009, and has been a financial journalist since 2011. He holds a degree in Business Administration and has experience producing real-time news, from both buy-side and sell-side, as well as for retail traders, brokers and service providers. Steves' work has appeared in a variety of online publications including FX Street, NewsBTC, FinanceFeeds, and The Industry Spread. Rick has great interest in the dynamics of the trading industry. The never-ending clash between technology, economics, regulation, and more importantly, the people.
