Exchange-traded fund issuers are once again venturing into crypto territory that regulators had recently steered them away from.

VanEck, Roundhill and Volatility Shares are among a half dozen issuers that have submitted applications for Ether-futures ETFs since Friday, according to documents filed with the US Securities and Exchange Commission. Some of the latest attempts come from companies like Bitwise that pulled their applications for similar funds in mid-May.