S2E16 — Polymarket, Kalshi and the People Who Knew First

A US Army sergeant bet roughly $33,000 on Polymarket on an arrest he had just been briefed on, and turned it into the price of a house. A Google engineer read his own company's unpublished data and moved about $1.2 million into a private wallet.

On a public blockchain, both men left a trail the FBI could follow to the cent. That is the paradox at the centre of prediction markets: the transparency that makes them exploitable is the same transparency that makes them honest. Between September 2025 and April 2026, combined monthly volume on these prediction markets climbed from under $5 billion to about $24 billion, and in October 2025 the parent of the New York Stock Exchange committed around $1.6 billion to the largest of them.

Aman Narain and Zubin Vandrevala break down how prediction markets went from a forgotten Wall Street betting ring to information infrastructure, and the harder question beneath the boom: when a market knows before the news does, is the system working perfectly, or is it being robbed?

Key takeaways:
1. The transparency that makes these markets exploitable is exactly what makes them honest: the engineer who hid behind a wallet was traced by the same chain he trusted.
2. The political framing is a myth. On Kalshi, 80% of volume is sports and just 4% is politics.
3. ICE bought the data, not the casino: roughly $1.6 billion for a live probability feed it can sell to every bank and hedge fund on its network.
4. Volumes ran from under $5 billion a month to about $24 billion in seven months, with Piper Sandler projecting $8 billion in annual revenue by 2030.
5. A prediction market is not an oracle but a mirror, only as honest as the room it is in.

Topics covered:
- The two cold-open exploits: a Fort Bragg sergeant and a Google engineer who bet on what they already knew
- The intellectual lineage: Hayek on price as information, Hanson's futarchy, Tetlock's superforecasters
- Wall Street's unregulated political betting ring, and the $10m wagered on the 1916 election
- The modern revival: the Iowa Electronic Markets, Intrade's collapse, and the fall of PASPA
- How a prediction contract actually works, and the passport-versus-wallet divide between Kalshi and Polymarket
- The full board: Polymarket, Kalshi, PredictIt, Manifold, Metaculus, Robinhood, Interactive Brokers and DraftKings
- The data that reorders the story: prediction markets are now mostly a sportsbook in a derivatives licence
- The three forces behind the 2024-2026 boom: the KalshiEX ruling, the GENIUS Act, and a presidential endorsement
- ICE's ~$1.6 billion move on Polymarket, and why it bought the data and not the gambling
- The prosecution: four insider cases, reflexivity, and gambling at derivative scale
- The bull case in three layers: parametric insurance, macro hedging, and information infrastructure

Chapters:
Referenced in this episode: US Army Master Sergeant Gannon Ken Van Dyke and Operation Absolute Resolve; the Google engineer "AlphaRaccoon" and the Year in Search exploit; the Israeli Air Force major and the June 2025 Iran briefing; the MrBeast editor's $4,000 Kalshi trade and $20,000 fine; Friedrich Hayek, Robin Hanson and futarchy, Philip Tetlock and the Good Judgment Project; the Wall Street curb-market and Tammany Hall betting ring, the 1896 and 1916 elections, and Governor Charles Evans Hughes; the Iowa Electronic Markets and their 1.34-point average error; Intrade and John Delaney; Murphy v NCAA; Polymarket on Polygon and Kalshi as a CFTC-designated contract market; PredictIt and Victoria University of Wellington; Manifold, Metaculus and Augur; Robinhood, MIAXdx and Susquehanna; Interactive Brokers and ForecastEx; DraftKings, Railbird and DKeX; KalshiEX v CFTC and CFTC chair Michael Selig; the GENIUS Act; ICE / Intercontinental Exchange and Jeffrey Sprecher; Piper Sandler's $8bn-by-2030 estimate; Boaz Weinstein and Saba; the 12 January 2026 single-day record of $701.7m; the Arizona pre-emption ruling and Minnesota Governor Tim Walz's ban.

Related episodes: S2E14 — Machines with Wallets, for the stablecoin-rails and GENIUS Act thread; [TBD — the Mastercard / BVNK stablecoin episode, confirm number].

Hosted by:
Creators & Guests

• Aman Narain - Host
• Zubin Vandrevala - Host

Aman Narain writes at amanwhoblogs.substack.com. Zubin Vandrevala is your payments provocateur.

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For information and entertainment only. Not financial advice.

Transcript:
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