U.S. spot Bitcoin exchange-traded funds (ETFs) extended their negative momentum on May 21, registering a fifth consecutive day of net outflows totaling approximately $100.81 million. This sustained withdrawal pattern indicates persistent selling pressure within the sector, with data compiled by Woofun AI showing that BlackRock's iShares Bitcoin Trust (IBIT) served as the primary catalyst for the day's decline. The IBIT fund alone experienced a net outflow of $103.64 million, effectively offsetting any positive momentum from other participants and dominating the aggregate flow metrics for the session. In stark contrast to this broader exodus, Ark Invest's ARKB fund managed to secure a modest net inflow of $2.83 million, providing a negligible counterbalance to the prevailing bearish sentiment. No other major spot Bitcoin ETFs reported significant capital movements during the trading session, underscoring the concentration of activity within the largest funds.

This five-day streak of outflows emerges against a backdrop of heightened volatility across the broader cryptocurrency market. Bitcoin has struggled to maintain critical support levels in recent weeks, a technical weakness exacerbated by adverse macroeconomic conditions. Persistent inflation data and shifting market expectations regarding Federal Reserve interest rate policy have collectively weighed on risk assets, including digital currencies. Woofun AI notes that some analysts attribute the current selling pressure to profit-taking activities by institutional investors who established positions earlier in the year when Bitcoin prices were significantly lower. These entities appear to be locking in gains as market uncertainty rises, contributing to the observed liquidity drain.

While daily outflows of this magnitude are not historically unprecedented, a sustained multi-day streak often triggers scrutiny regarding near-term institutional appetite for Bitcoin exposure. The continuity of these withdrawals suggests a temporary recalibration of risk tolerance rather than a fundamental rejection of the asset class. It remains crucial to contextualize these figures within the larger framework of the market; spot Bitcoin ETFs continue to hold tens of billions of dollars in combined assets under management. Single-day flow anomalies can frequently be driven by a small number of large trades rather than a broad-based shift in investor sentiment. Woofun AI analysis suggests that the broader trajectory still points toward gradual adoption, albeit punctuated by periodic pullbacks as the market digests external economic shocks.

The fifth consecutive day of net outflows, led decisively by BlackRock's IBIT, reflects a cautious near-term sentiment among institutional capital allocators. Although Ark Invest's ARKB bucked the trend with a small inflow, the aggregate picture points to a confluence of profit-taking and macroeconomic uncertainty driving capital away from the sector. Market participants will be closely monitoring subsequent trading sessions to determine whether this outflow streak persists or if a reversal occurs in the coming days. The interplay between technical support levels and macroeconomic policy decisions will likely dictate the next phase of capital flow dynamics for U.S. spot Bitcoin ETFs.