A lot of controversy on this, and a lot of bad takes too, so let's unpack it.
First, the fact that most of the volume comes from orders of the same size (~$5.4k ETH, $2.5k BTC) doesn't say much about whether it's wash trading. It could be a maker posting that size at the top of the book and getting picked off by a taker who hits the full quote every time. Makers are often paid by exchanges, so they have an incentive to stay in the book even if they lose a small edge.
To tell whether it's wash trading, only one thing doesn't lie: markouts. For those who don't know, markouts answer the question: where did the price go after you traded? Positive = you bought before it went up (or sold before it went down), negative is the reverse.
There are three groups of takers when we look into the data:
• orders sized exactly to the fixed quote (roughly $5.4k ETH, $2.5k BTC): 54% of ETH, 44% of BTC notional
• bigger sweeps that also hit that quote
• everyone else
So first, what real taker edge looks like. When Binance jumps, normal Kalshi takers hit the stale quotes ~65 ms later (≈ the Tokyo - Binance →Ohio - Kalshi hop). Their edge is locked in within 500 ms, and the markout shows it: +0.41 bps at 1s on ETH.
Now let's look into where it hurts. We split the fixed-size takers from the rest, and plot when their orders arrive after a Binance move of more than 3 bps (2 bps on BTC). That's where you'd expect arbitrage, and you see it clearly in the "other" trades: a peak about 65 ms after the Binance move, close to the latency between the two locations. The surprise is that the fixed-size trades are almost flat. So whatever edge that taker has, it isn't latency. (First graph of the tweet)
Kalshi's article also leans on
@OctopusTakopi's numbers to say the taker has edge, but that $98k is measured around 30s. That makes no sense. The only edge that could explain this taker not being wash trading is very short-term latency arbitrage between Binance and Kalshi. If you had a longer edge, at 30s or more (much noisier and harder to find), you'd trade it on the most liquid venue, where you can put on far more size. And at 1 second, where a latency edge would show, it doesn't: 0.00 bps ETH, −0.07 BTC. BTC is negative 19 of 19 days. Same answer if you use Kalshi's own mid instead of Binance's. The "profit" only shows up after 5s: around +0.12, at 30s it's +0.13 bps on ETH and +0.12 on BTC, and it never goes above +0.17 bps at any horizon. That's not information. Their direction matches the last visible Binance tick 59 to 64% of the time, and a naive "follow the last tick" rule earns the same drift - which means no real alpha. (Second graph of the tweet)
No one holds 30s of risk for 0.1 bps unless trading is free. Which raises the question: is it? Kalshi says members have a fee holiday. Its CFTC filing says takers net 0.3 bps and makers are paid 0.3. At 0.3 the fixed-size taker loses at EVERY single horizon.
tldr: the fixed-size taker has no latency edge. Its only "profit" shows up after 5s, is worth ~0.1 bps, and a naive momentum rule gets the same. If it pays 0.3 bps in fees, it loses money, and quite a lot given the volume. The tape has no account IDs, so this can't prove who's behind it, but "profitable for the taker" certainly doesn't hold up.
i thought more about it. beni, sorry for being a dick. i shouldn't have attacked you personally. it was cocky and unnecessary, and i should have stuck to the facts.
i do want to clarify one thing: our incentives pay for liquidity, not wash trading. the claim that we’re incentivizing wash trading is incorrect, but i should have explained why instead of making it personal.
this has made clear we need to do a better job explaining how our incentives work and the safeguards we have in place. we’ve laid out the full context here:
news.kalshi.com/p/the-facts-…