The Commodity Futures Trading Commission is examining trading in Kalshi’s ether perpetual futures market, where one repeating order size has come to dominate volume, The Wall Street Journal reported Tuesday. The regulator is reviewing the activity before deciding whether to open an enforcement investigation, according to a person familiar with the matter cited by the Journal.

The Journal’s analysis of public trading data found nearly 1 million trades of almost identical size in the market, with more than a third of trades in recent weeks clustered around $5,500. That pattern accounted for more than $5 billion in ether perp volume over the past month. Jump Trading and Wintermute were among the firms involved, according to the Journal.

This story is an excerpt from the Unchained Daily newsletter.

Kalshi is one of the first exchanges to offer crypto perpetuals under US regulation, so whether its reported volume reflects genuine demand could impact how traders and investors read the business. The review comes as the company seeks approval for similar contracts tied to individual US stocks, and after CFTC staff warned in August that steep volume-based rewards can push participants to trade simply to hit targets.

In a blog post Tuesday, Kalshi said the fixed-size trades reflect a single market maker paid to keep resting bids and offers of a set size on the book, which faster traders repeatedly picked off. The takers, which Kalshi said “were hundreds of distinct traders,” came out ahead, and the exchange pointed to roughly $98,000 in taker profit in one of the critics’ own analyses as evidence against wash trading, meaning trades with no real economic purpose.

Kalshi said self-trading is mechanically blocked, trading with a partner is surveilled and banned, and its liquidity programs pay for resting orders rather than volume. Self-clearing members currently get back exactly what they pay in perp fees under a temporary rebate launched in July, and Kalshi said a net-zero maker and taker fee schedule circulating online is not live.

The allegations surfaced in a Sept. 20 thread by Beni, a co-founder of research firm Stealth Neolab, who flagged the repeating trades as 48% to 58% of ether perp notional volume on four days between Sept. 16 and Sept. 20. Kalshi launched crypto perps on June 3 after the CFTC approved its first contract on May 29, and says it has since drawn more than 350,000 lifetime perp traders, with open interest doubling over the last 30 days.

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