On May 21, Cboe BZX submitted 19-b4 amendments concerning five proposed Ethereum ETFs, significantly boosting the likelihood of approval for each fund. This news coincided with a sudden increase in approval odds on Polymarket, rising from 10% to 70% by May 31. Bloomberg ETF analyst James Seyffart remarked that these filings validate earlier rumors and speculation.

While Seyffart acknowledged that the approval process is still lengthy, as the SEC must issue approval orders on the 19b-4 filings followed by S-1 registration statements, he suggested that each fund may not launch for "weeks or more."

Seyffart and colleague Eric Balchunas raised approval odds to 75% after reports of upcoming amendments from their sources. Similarly, FOX Business reporter Eleanor Terret supported the reports based on her own sources.

The amendments pertain to proposals from Fidelity, VanEck, Invesco, Galaxy, Ark Invest, 21 Shares, and Franklin Templeton. However, not all pending applications are covered, as Grayscale aims to convert its Ethereum Trust (ETHE) to a spot ETF on NYSE Arca, and BlackRock and Hashdex plan spot Ethereum ETFs on Nasdaq.

The SEC's decision on VanEck's spot ETH ETF is expected on May 23, with the possibility of approving multiple similar proposals simultaneously.

The amendments also specify critical aspects of each ETH ETF, including the exclusion of Ethereum staking by the trust, fund, sponsor, custodian, and other parties. Some applicants initially proposed staking but later removed it from their S-1 statements. Additionally, the filings confirm that each fund will use cash creation and redemptions instead of in-kind transactions, which could influence the SEC's decision on ETH ETFs.