Which BTC ETF led outflows?

TLDR

BlackRocks iShares Bitcoin Trust (IBIT) led the biggest single-day Bitcoin ETF outflows in the past week.

1. On 4 Dec, IBIT logged about $113 million in net outflows; Fidelitys FBTC followed with $54.2 million (IBIT figure, FBTC figure).
2. On 8 Dec, Grayscales GBTC led daily outflows at $44.03 million, while IBIT saw inflows (GBTC and IBIT flows).
3. Recent outflows are concentrated and often reflect unwinding of basis trades, not broad capitulation (flow concentration context).

Deep Dive

1. Biggest Outflow Day

The heaviest outflow day in the last week was 4 Dec, and IBIT led redemptions.

1. Spot Bitcoin ETFs shed $194.6 million then, with IBIT accounting for ~$113 million of outflows (overview and IBIT figure).
2. Fidelitys FBTC recorded $54.2 million of outflows the same day, confirming concentration among the largest funds (FBTC figure).

2. Most Recent Daily Leader

Leadership rotated later in the week.

1. On 8 Dec (ET), US spot Bitcoin ETFs posted $60.48 million net outflows; GBTC led outflows at $44.03 million, while IBIT uniquely had $28.76 million inflows (daily breakdown).
2. This divergence highlights issuer-specific dynamics and investor rotation across wrappers.

3. Why Outflows Concentrate

Recent outflows have been concentrated, often tied to arbitrage unwinds rather than broad panic selling.

1. Analysis indicates the multi-week outflow wave was driven largely by basis trade unwind; BlackRocks share of recent weekly outflows was outsized versus its AUM share (arb unwind context).
2. On other days, IBIT itself led outflows by value, including a ~$113 million single-day outflow on 4 Dec (IBIT detail).

Conclusion

This weeks outflows were led by IBIT on the heaviest day (4 Dec), while GBTC led the most recent daily outflows (8 Dec). The leadership rotates and is often driven by arbitrage and funding rather than broad capitulation, so tracking IBIT, FBTC, and GBTC together gives the best near-term signal on Bitcoin ETF demand.