If at first you don't succeed, try try...to make it unhackable. That seems to be the response from a pair of fund shops that were rebuffed by the Securities and Exchange Commission when they first tried to launch bitcoin exchange-traded funds.

VanEck and SolidX, which attempted to launch their own individual bitcoin ETFs, have teamed up to launch a physically-backed bitcoin ETF. The SolidX Bitcoin Trust will fly under the ticker XBTC if it gets approved, according to filings. VanEck will be in charge of marketing and SolidX will be the sponsor, though, it will use VanEck's MVIS OTC Bitcoin Index to value the assets.