bitcoin spot exchange-traded funds (ETFs) began trading in the US on January 11, investors have poured $12.1 billion (£9.7 billion) into them, of which over 80% has gone to either BlackRock's iShares brand or Fidelity Investments.

"They're both massive asset managers with incredible reach and the strongest distribution networks […] everyone is a client of iShares, and other firms don't have platforms like Fidelity," says Bryan Armour, director of passive strategies research for North America at Morningstar.

Meanwhile, the Grayscale Bitcoin Trust, now ETF – the favoured crypto-tracking ETF for investors before the advent of spot bitcoin funds – has seen $17.2 billion go out the door.

Grayscale, which heavily lobbied the Securities and Exchange Commission (SEC) for permission to launch spot bitcoin ETFs, has seen the assets in its fund plummet to $17.6 billion from $27.2 billion in February.

"It’s been a very successful launch for spot bitcoin ETFs overall, albeit with some wild price swings," says Armour.

"The nine new bitcoin funds gathered significant inflows, while Grayscale's newly converted ETF saw major outflows."

Net Inflows for Spot Bitcoin ETFs

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