Related: As Bitcoin Plunges, Here are 5 Historic Market Bubbles to Remember

A major problem with bitcoin ETFs, as far as the SEC is concerned, is the potential for bitcoin thefts. Over the digital currency’s history, exchanges and individual users have been victimized by nefarious hackers that steal investors’ assets, something that does not happen with traditional securities, including ETFs.

Clayton “added that the underlying assets in existing ETFs are not at risk of ‘theft or disappearance’—implying he does not believe this is the case for proposed digital currency ETFs, notwithstanding the crypto industry’s recent focus on secure custody offerings,” reports Fortune.

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