As well as proving popular with retail investors, bitcoin ETFs have caught the attention of hedge fund majors including Millennium Management, Schonfeld Strategic Advisors and Point72 Asset Management, according to a report by Bloomberg.

The report cites regulatory 13F fillings made with the Securities & Exchange Commission as revealing that all three had made bitcoin ETF purchases following their debut earlier this year, with Millennium emerging as the largest bitcoin ETF investor, with $1.9bn invested – $844.2m in BlackRock’s iShares Bitcoin Trust (IBIT), $806.7m in Fidelity’s Wise Origin Bitcoin Fund (FBTC), $202m in the Grayscale Bitcoin Trust (GBTC), $45.0m in the ARK 21Shares Bitcoin ETF (ARKB) and $44.7m in the Bitwise Bitcoin ETF (BITB).

Schonfeld Strategic Advisors, a hedge fund with $13bn in AUM, was the second-largest spot bitcoin ETF investor at $479m – $248m in IBIT and a $231.8m in FBTC.

New York-based Boothbay Fund Management is another hedge fund to disclose a sizeable bitcoin ETF holding, declaring a total $377m exposure – $149.8m in IBIT, $105.5m in FBTC, $69.5m in GBTC and $52.3m in BITB.

Others institutional investors among the approximately 1,000 13F filers to disclose bitcoin ETF holdings include the State of Wisconsin Investment Board and the Bank of Montreal, according to Bloomberg's analysis. Market makers that trade the ETFs, including Citadel Securities and quant-trading firm Susquehanna International Group, also reported holdings of the funds.

BlackRock’s IBIT has proved the most popular with 13F filers, with around 420 firms disclosing holdings, while more than 230 filers disclosed holdings in FBTC.