Gambling Insider reported that, across 5.35 million trades in Kalshi’s ether perp between Aug. 1 and Sept. 30, transactions clustered around six near-fixed dollar sizes accounted for 55.9% of the contract’s $17.56 billion in notional value. Kalshi had said the pattern was consistent with a market maker posting fixed-size resting orders while faster traders repeatedly executed against stale quotes as ether moved elsewhere.
If that account fits the trading, the concentrated orders should have shown a clear edge against a spot-implied ether price. Gambling Insider’s test found much less than that. The fixed-size traders beat the spot-implied price on 33% of transactions, versus a 35% benchmark for random buy-or-sell directions at the same moments and spreads. Allowing up to one second for timing differences improved the result to 39%, against a 36% chance benchmark.
Other traders on the same market did far better under that same one-second allowance, beating the spot-implied price on 54% of trades against a 42% benchmark.
That does not establish what caused the pattern, and Gambling Insider is explicit about that. It also does not establish wash trading. None of the three experts consulted by the publication concluded that wash trading had occurred.
What it does do is weaken the tidy version of events in which concentrated traders were mostly picking off stale quotes. Rajiv Sethi, a Barnard economist who had advanced a similar “tolerated sniping” explanation, told Gambling Insider after reviewing the results: “I think only the account identifiers could settle this decisively, but I am starting to have doubts about my tolerated sniping explanation.”
The scale of the concentration is still the part that grabs you. Gambling Insider asked Kaiko to apply a comparable test to ether perpetual futures on Binance and Hyperliquid. Kaiko found the day’s most-traded size accounted for 1.68% of notional value on Binance’s ETH/USDT contract, 1.61% on Binance’s ETH/USDC contract and 3.79% on Hyperliquid. Kalshi’s comparable figure was 55.8%. Even its least concentrated day, at 9.3%, was above the highest daily concentration on the comparison contracts.
Thomas Probst, a research analyst at Kaiko, said the firm had not seen that degree of concentration at a single trade size on either venue. He added that a younger market with fewer participants can make the behavior of one large participant show up more strongly.
That caution matters. An unusual pattern is still just a pattern unless the underlying accounts show more. But Kalshi’s public explanation now looks less convincing on its own terms, because the traders behind those near-identical sizes did not perform like traders who were consistently exploiting stale quotes.
Kalshi declined to comment on the new analysis, according to Gambling Insider. The Wall Street Journal had previously reported more than $5 billion in almost one million near-identical trades in the contract and said the Commodity Futures Trading Commission was examining them, citing a person familiar with the matter.
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