Spot Bitcoin (BTC) exchange-traded funds (ETFs) are on a roll.

Data from crypto research platform SoSo Value shows that spot Bitcoin ETFs saw their second-biggest day ever on June 4th with a daily total net inflow of $886.7 million.

Its most successful day so far was on March 12th when daily total net inflow hit $1.05 billion.

The investment product already has a cumulative total net inflow of $14.85 billion as of June 4th and has only seen positive inflows since May 13th.

BlackRock’s iShares Bitcoin Trust (IBIT) has the highest inflow since listing with $17 billion, followed by Fidelity Wise Origin Bitcoin Fund (FBTC) with $9 billion. ARK 21Shares Bitcoin ETF (ARKB) is third with $3 billion, followed by Bitwise Bitcoin ETF (BITB) and Invesco Galaxy Bitcoin ETF (BTCO) with $2 billion and $317 million, respectively.

Spot Bitcoin ETFs have continued to attract investor interest since receiving the green light from the U.S. Securities and Exchange Commission (SEC) in January.

New data from Bitcoin brokerage firm River indicates that 12 of the 25 largest US hedge funds now collectively have over $2.6 billion in Bitcoin ETF exposure. Eleven of the 25 Registered Investment Advisors (RIAs) are also invested in the product.