U.S. Bitcoin ETFs have struggled over the past two weeks. According to new data from Farside Investors, the ten BTC index funds have seen more than a billion dollars in net outflows since June 10. The Grayscale Bitcoin Trust performed especially poorly, losing about $540 million. Another ETF provider also saw substantial outflows.

Fidelity's third-largest Bitcoin ETF lost BTC worth $385 million over the same period, despite again having the highest net inflows over the past two days. According to The Block, the U.S. financial giant's FBTC now holds 176,460 BTC. That's more than three times as much as the ETF provider in fourth place, Ark21Shares. In total, the ten BTC index funds raised $52.4 million last Tuesday and Wednesday. That's a positive but not a whole lot compared to other green days.

BlackRock on the ETF throne

In the long run, Bitcoin ETFs have been a great success. In the first three months after SEC approval alone, BlackRock and Fidelity's Bitcoin index funds had net inflows of $15.5 billion and $8.2 billion, respectively. Both products are among the best-performing ETFs ever. Currently, market leader BlackRock holds BTC worth $18.6 billion, while Grayscale still has $16.9 billion in BTC.

Unlike its competitors, BlackRock's iShares Bitcoin Trust also had net inflows again in the difficult second half of June, with $43 million flowing into the ETF. In late May, BlackRock knocked Grayscale off its throne. In total, U.S. Bitcoin ETFs now hold 865,000 Bitcoin, which is about 4.4 percent of the total BTC in circulation.