An SEC spokesperson declined to comment on the ether ETF proposals.

In January, the US securities regulator approved the simultaneous launch of 10 US spot bitcoin ETFs.

Four months later, BlackRock's iShares Bitcoin Trust (IBIT) holds significantly more assets than any other competing product, except for the converted Grayscale Bitcoin Trust ETF (GBTC). IBIT and GBTC have roughly $19 billion and $20 billion in assets, respectively.

Meanwhile, the VanEck Bitcoin Trust (HODL) manages about $700 million in assets.

Sigel argued that this time the SEC should allow VanEck to respond to the agency's comments first and that the proposed VanEck Ethereum Trust should be the first to reach the market.

“I fundamentally disagree with the approach of lining everyone up to go at the same time; that’s never how the process has worked,” Sigel said. “This administration seems to like to micromanage the distribution, favoring large incumbents, and we have an issue with that.”

The stock exchanges intending to list the ether ETFs amended their 19b-4 documents on Tuesday.

Industry watchers noted that even if the SEC approves these 19b-4 proposals, the launches might not be immediate.

Before any such funds can start trading, the SEC must also approve the S-1 registration statements filed by VanEck and other issuers—a process that could take weeks, according to some experts.