US Spot Bitcoin ETFs Deliver Best Week Since April, $1B Net Inflows

Demand for US spot Bitcoin exchange-traded funds (ETFs) surged this week, according to Bloomberg ETF analyst Eric Balchunas, reviving a narrative that had gone quiet after months of more inconsistent buying. At the same time, a recent security incident tied to Coldcard has put crypto self-custody back under the spotlight—an issue that some ETF investors may be weighing more carefully.

Balchunas said Saturday that the spot Bitcoin ETFs pulled in roughly $1 billion in net inflows for the week. He described it as the funds’ strongest performance since April and the third-best week since last October, when he referred to the phenomenon as Bitcoin’s “silent IPO.”

Key takeaways

• Bloomberg ETF analyst Eric Balchunas reports about $1 billion in weekly net inflows for US spot Bitcoin ETFs, the strongest since April.
• Balchunas framed the earlier October period as Bitcoin’s “silent IPO,” suggesting ETFs can pull in institutional-style demand without obvious market fanfare.
• A widely discussed Coldcard hardware wallet hack—connected to about $116 million stolen—has reignited concerns around the security burdens of self-custody.
• Balchunas said the hack could support the case for spot ETFs among investors wary of technical custody responsibilities, though he stressed the link is not proven.

Spot ETF inflows rebound after a softer stretch

The renewed buying matters because it helps clarify what has been happening beneath the surface of Bitcoin’s price action. Even when new capital enters through ETFs, the relationship to spot market momentum can be muted if supply is being sold off concurrently—something that investors have been trying to explain over recent months.

Balchunas tied this week’s momentum to the contrast with prior periods. In his view, earlier demand dynamics contributed to a broader “changing of the guard,” where earlier Bitcoin holders increasingly monetized positions as ETF and other institutional inflows grew. He linked this to the term popularized by investor Jordi Visser in November: Bitcoin’s “silent IPO.”

The phrase captures an idea that the ETF ramp behaves less like a noisy retail mania and more like a steady institutional distribution channel—keeping Bitcoin from reacting dramatically while significant flows accumulate.

In that context, the standout feature of this week is not simply that inflows turned positive, but that they represent the strongest showing since April and rank among the best weekly results since last October. That suggests the ETF pipeline is capable of re-accelerating, even if the broader period has been uneven.

Coldcard hack revives the self-custody debate

While ETF flows grabbed attention, the week’s backdrop included a major security incident involving Coldcard, a Bitcoin hardware wallet from Coinkite. The exploit is reported to have led to the theft of roughly $116 million worth of Bitcoin, according to prior reporting that connected the theft to a vulnerability in how affected devices generated wallet keys. Attackers allegedly compromised funds by targeting wallets created using vulnerable firmware.

On Friday, Balchunas suggested the aftermath could influence investor behavior. In a discussion carried in a separate report, he argued that the security and technical responsibilities of self-custody may push some investors toward spot Bitcoin ETFs, particularly those who prefer to outsource custody and operational risk to traditional market structures.

Crucially, Balchunas framed the potential connection as speculative. He acknowledged that correlation does not prove causation. Still, he said, “long-term I can’t imagine there aren’t some who migrate over,” implying that even partial behavioral shifts—if they occur—could show up in ETF demand over time.

What investors should watch: flows, behavior, and persistence

This is where the story becomes more than a one-week data point. ETF inflows are typically driven by a mix of institutional allocation patterns, advisor workflows, and broader risk appetite. A temporary rebound can happen without signaling a structural turn. However, Balchunas’s framing of both the “silent IPO” period and the current resurgence suggests he believes the market is cycling between phases of strong demand and quieter distribution.

For traders and long-term allocators, the practical question is whether this week’s improvement marks a continuation or a rebound followed by another slowdown. The “strongest since April” and “third-best week since last October” descriptors indicate a meaningful spike relative to recent history, but the durability of that spike will depend on whether ongoing capital inflow stays steady.

Meanwhile, the Coldcard incident adds a different kind of variable: perceived operational risk. Hardware wallets are widely used precisely because they reduce exposure to exchange custody failures, but high-profile vulnerabilities can change how comfortable some investors feel handling keys themselves. Balchunas’s argument is that—over time—investors uncomfortable with custody mechanics may consider ETFs a simpler alternative.

Yet, it’s also possible that self-custody concerns are already priced into broader behavior, meaning the effect on ETF demand may be gradual rather than immediate. That makes future inflow trends the key test: if inflows keep outperforming earlier weeks consistently, the market impact of custody-related security narratives could become clearer.

Read together, the two threads—ETF demand rebounding and custody concerns resurfacing—underline a single theme: Bitcoin’s access channels are still evolving. Spot ETFs offer a regulated wrapper, while self-custody remains the route for those who want direct key control. The next phase will likely hinge on how quickly investors shift between those modes and whether ETF inflows sustain at elevated levels beyond this week.