Things are going well at BlackRock: the iShares Bitcoin Trust is creating a furor and could soon become the market leader in Bitcoin ETFs. Even CEO Larry Fink didn't see this coming.

The CEO of the world's largest asset manager, BlackRock, is "pleasantly surprised" by the groundbreaking success of its Bitcoin ETF. He is also "very optimistic" about Bitcoin's long-term profitability.

In a interview with Fox Business, Larry Fink once again stressed the importance of Bitcoin's own ETF: "IBIT is the fastest growing ETF in the history of ETFs. Nothing has ever grown in value as fast as Bitcoin. Nothing has ever grown in value as fast as IBIT."

BlackRock's Bitcoin ETF has seen impressive inflows of $13.5 billion since its approval by the SEC on Jan. 11. According to data from Farside Investors flowed more than $323 million into the iShares Bitcoin Trust again yesterday.

"We would never have predicted before the filing that we would see this kind of demand in the retail sector," said a clearly pleased Larry Fink.

According to BitMEX Research with the IBIT, BlackRock has a total of $17.1 billion in Bitcoin and needed just two months to reach the $10 billion mark. The first gold ETF took two years to reach this milestone.

Of all the Bitcoin spot ETFs currently authorized, BlackRock is only behind the Grayscale Bitcoin Trust in terms of Bitcoin investments. It currently holds $23.6 billion in BTC, but the custodian could be replaced in the near future.

The GBTC is constantly losing Bitcoin, mainly due to high fees. In the past ETF negative week more than $2 billion worth of BTC flowed out of the Grayscale fund, which still has a 41.7 percent market share.

The opposite is true of BlackRock's Bitcoin ETF. According to Dune IBIT already has a 29.6 percent market share, with a clear upward trend. If this trend continues, BlackRock will likely be the market leader within a few weeks.