Spot Ethereum ETF predictions have caused losses for some Polymarket users, leading to ongoing complaints against the decentralized platform. Over $13.2 million was bet on whether the Ethereum ETF application would be approved by May 31. However, the approval process remains unclear.

The market concluded with a "Yes" result on May 23 after the SEC gave the green light to multiple Ethereum ETF applications via 19b-4 forms. This result was briefly contested but ultimately upheld.

"No" voters argue that without an approved S-1 Form, the "Yes" result is incorrect since both 19b-4 and S-1 forms are required for ETF applications to start trading. Analysts note that the SEC's approval of S-1 forms, which some "No" voters might have invested in, could take months.

A prominent user, JustKen, who bet on "No" and later renamed themselves RevengeTour19B4, highlighted a tweet from VanEck's crypto asset research head Matthew Sigel, stating that ETFs aren't fully approved without both forms. Bitwise investment chief Matt Hougan echoed this on the Unchained podcast, describing the need for both forms as a "nuclear key scenario."

Details on the Process Meanwhile, some winning "Yes" predictors argue that the market only required SEC approval, not the actual trading of the ETF funds by May 31. They assert that 19b-4 approvals are considered final and that S-1 Form approvals typically follow.

Risk Labs, the company behind the blockchain oracle platform UMA that addresses such informational disputes, and Adventure One QSS Inc., Polymarket’s developer, did not immediately respond to requests for comment.