saw their strongest weekly inflows since April following a hack that renewed attention to the risks of storing digital assets, Bloomberg reports.

These ETFs attracted more than $850 million last week. The surge in inflows followed the disclosure of a hack into Coldcard wallets manufactured by Canadian firm Coinkite Inc., which resulted in the theft of approximately $130 million in Bitcoin. This prompted some analysts to speculate that investors may be shifting toward regulated Wall Street crypto products.

"The Coldcard hack could make spot Bitcoin ETFs a more attractive option for some investors, including even some long-standing Bitcoin holders," said Eric Balchunas, an analyst at Bloomberg Intelligence.

Cold wallets have long been considered one of the most secure ways to store digital assets. These physical devices are kept offline and use secret codes, allowing owners to transact cryptocurrency. This isolation from the internet is intended to make assets much less vulnerable to cyberattacks.

The Coinkite incident has challenged this dogma. A vulnerability in some versions of Coinkite's firmware made the data used to protect some wallets more predictable than expected, allowing attackers to gain control of the affected wallets and steal bitcoins without even having access to the Coldcard devices themselves.

"We are fully focused on helping affected customers," Coinkite said in a statement to Bloomberg News on Thursday.

The hack is the latest blow to Bitcoin holders, who have already seen the cryptocurrency's price fall by approximately 50% since its October all-time high. Bitcoin has traded in a narrow range of $60,000–$67,000, with relatively muted movements since June.

This makes the surge in demand for ETFs in recent days more noticeable, as the influx has not been accompanied by a large-scale rally.

Demand indicates that "the ultimate coin is migrating from self-custody to institutional environments, where it becomes a bound, distributed supply," noted Rajeev Soni, head of international portfolio management at Wave Digital Assets.

Moving to ETFs doesn't eliminate risk. A crypto ETF custodian can still suffer a hack, even though large firms typically have dedicated security teams and extensive safeguards for client assets.

Investors are also giving up the direct control that self-custody offers for Bitcoin—many have become wary of it after years of exchange collapses, bankruptcies, and fraud in the crypto sector.

"There's no guarantee against losses if an ETF custodian is ever compromised, but such an incident would likely immediately trigger regulatory scrutiny and law enforcement investigations," Balchunas said.

This could give some investors more confidence in entrusting their Bitcoin investments to large financial firms, he added.