On August 20, according to The Block, citing sources familiar with the matter, before Cboe BZX removed the Solana ETF-related Form 19b-4 from its website, the SEC had held talks with potential Solana ETF issuers and expressed concerns about Solana's potential status as a security. After discussions, the SEC and Cboe agreed not to file Form 19b-4 with the Federal Register. The 19b-4 filings that Cboe filed on behalf of ETF issuers over the weekend are no longer available on the exchange's website. They are also not currently in the Federal Register. For an ETF to be approved, Form 19b-4 must first be approved and the S-1 registration statement must take effect. The S-1 registration statement for VanEck's Solana ETF still appears on the SEC's filing system, EDGAR. The S-1 registration statement file for 21Shares no longer appears in search results, but the direct link still works. The source said the SEC's stance was not surprising to the issuer given that it had previously referred to Solana as a security in multiple court filings. They expect new filings or revisions to 19b-4 in the future to try to prove that Solana is not a security, the source said. Although both bitcoin and ethereum spot ETFs have cleared regulatory hurdles and started trading, most market observers had expected the SEC to be more reluctant to approve the new Solana fund.