On Thursday, U.S. spot bitcoin exchange-traded funds (ETFs) experienced their 13th consecutive day of net inflows, collectively drawing in $48.71 million. Notable fund movements were observed in bitcoin ETFs managed by Fidelity, Ark Invest, and 21Shares.

Fidelity’s FBTC led the pack with significant net inflows worth $119 million. In contrast, Ark Invest’s ARKB witnessed a substantial net outflow of nearly $100 million, marking its largest outflow since its debut in January. This data comes from SoSoValue, highlighting the contrasting investor behaviors towards these funds.

BlackRock’s IBIT, the largest spot bitcoin fund by net assets, recorded a modest net inflow of $2 million. Grayscale’s GBTC, which recently became the second largest spot bitcoin fund, saw no net inflows. Bitwise’s BITB attracted $26 million, while Invesco and Galaxy Digital’s bitcoin ETF reported net inflows of $2 million.

Rachael Lucas, Crypto Analyst at BTC Markets, commented on the unusual spot bitcoin ETF flows. She attributed them to investor uncertainty regarding the Federal Reserve's interest rate path, especially with significant economic reports due from the U.S. on May 31.

“If U.S. inflation numbers exceed expectations and personal income and spending trends rise, it could dampen investor optimism about a potential Fed rate cut in September. A more hawkish Fed could negatively impact demand for riskier assets, including bitcoin and related ETFs,” Lucas explained.

Over the past 13 days, U.S. spot bitcoin ETFs have seen total net inflows exceeding $2 billion. This marks their second-longest positive streak since their listing, surpassed only by the 17 straight days of net inflows that began in January. Despite this, the total volume of flows in these ETFs remains significantly smaller than their peak in March, according to data from The Block’s data dashboard.

In related news, Grayscale filed its amended S-1 registration statement for its spot Ethereum fund on Thursday, following BlackRock’s filing a day earlier. More S-1 filings are anticipated as the U.S. Securities and Exchange Commission (SEC) has requested issuers to submit their forms by Friday.