Demand for US spot Bitcoin exchange-traded funds (ETFs) rebounded sharply this week, signaling renewed investor appetite after months of uneven flows, even as uncertainty persists around digital asset regulation and the security of crypto self-custody.

On Saturday, Bloomberg ETF analyst Eric Balchunas said the spot funds attracted roughly $1 billion in net inflows for the week, their strongest showing since April and third-best week since last October — a period he referred to as Bitcoin’s “silent IPO.”

Source: Eric Balchunas

The term was popularized by investor Jordi Visser in November to describe what he viewed as a changing of the guard among Bitcoin holders. Under the theory, early investors were selling into growing demand from ETFs and other institutional buyers, creating enough supply to keep Bitcoin subdued despite substantial new capital entering the market.

That distribution coincided with a deterioration in ETF flows compared with earlier periods of stronger demand, making this week’s rebound particularly notable.

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Coldcard hack puts self-custody in focus

The rebound has also followed a major security incident involving Coldcard, a popular Bitcoin hardware wallet developed by Coinkite, that resulted in roughly $116 million worth of Bitcoin being stolen. The exploit was linked to a flaw in how affected devices generated wallet keys, allowing attackers to compromise funds held in wallets created using vulnerable firmware.

On Friday, Balchunas suggested the incident could ultimately strengthen the appeal of spot Bitcoin ETFs among investors who are uncomfortable with the technical and security responsibilities associated with self-custody. He pointed to the surge in ETF inflows following the hack as a potential, though unproven, link.

While acknowledging that correlation does not imply causation, Balchunas said, “long-term I can’t imagine there aren’t some who migrate over,” referring to investors potentially shifting from cold storage to ETFs.

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