BlackRock filed on Monday, October 20 for the iShares Bitcoin Managed Protect ETF, a fund designed to cap how much an investor can lose when bitcoin falls, as CoinDesk first reported. The filing arrives with bitcoin trading near $82,845, roughly 52% below its roughly $126,000 record high, and it marks the third distinct bitcoin wrapper the world’s largest asset manager has taken to market in under three years.
A three-step ladder
The progression reads like a deliberate segmentation of one asset class. First came the iShares Bitcoin Trust (IBIT), the spot fund launched with the 2024 U.S. ETF wave that now manages more than $65 billion. Then, in June, came the BlackRock Bitcoin Premium Income Fund (BITA), an actively managed vehicle that owns bitcoin and IBIT and writes covered calls against about a quarter to a third of the portfolio to spin off monthly income. The new filing adds a third rung: upside participation with a floor.
“The Fund seeks to provide upside exposure to the iShares Bitcoin Trust ETF and/or similar bitcoin exposure up to an approximate limit, while seeking to provide a level of downside protection,” BlackRock said in the filing.
That language tracks the strategy Jay Jacobs, BlackRock’s U.S. head of equity ETFs, described when the firm built out its income products: investors, he said, were “looking to generate some amount of income off of still having a mostly large, mostly long position to bitcoin.” The new filing extends the same logic from income to capital preservation, the natural next sell to a base of holders sitting on the drawdown.
The precedent is a $15 million rival
BlackRock is following a structure pioneered by a far smaller firm. Calamos Investments rolled out a first trio of protected bitcoin ETFs in the opening months of 2025; the funds either fully shield investors from losses or cap them at 10% or 20%, parking about 90% of assets in U.S. Treasuries and the remainder in bitcoin-linked options. Its Calamos Bitcoin Structured Alt Protection ETF October (CBOO) has lost about 1% since its one-year protection period began in October 2025, a figure a Calamos spokesperson provided, even as spot bitcoin fell by half.
Those funds attracted between $10 million and $15 million over several weeks as of May, Matt Kaufman, Calamos’ head of ETFs, said at the time, a rounding error next to IBIT’s asset base. What the filing signals is that the product category works well enough for the firm run by Larry Fink to want it in its own lineup, where the same structure would ride a distribution machine that turned IBIT into the largest U.S. spot bitcoin fund.
For readers tracking bitcoin through funds and ETFs, the open items to watch are the protection level, the upside cap and the fee, none of which the Monday filing discloses.
