BlackRock (NYSE: BLK) filed on October 19 for a Bitcoin ETF that aims to cap initial losses near 10% while limiting gains. The filing landed as its spot fund, IBIT, led the strongest day for U.S. Bitcoin ETF inflows in a month.
The Brief
- BlackRock’s proposed iShares Bitcoin Managed Protection ETF, ticker PBIT, would get its Bitcoin exposure through options on IBIT.
- The fund would buy IBIT calls struck near 90% of the reference value, setting its initial loss floor before fees.
- IBIT took in $665.2 million that day, its biggest daily inflow since October 7, 2025, according to SoSoValue.
- U.S. spot Bitcoin ETFs drew $526.6 million in net inflows on the session, their best day since September 22.
PBIT trades Bitcoin upside for a loss floor
BlackRock Fund Advisors would run PBIT through three overlapping tranches of FLEX options on IBIT. The structure appears in the registration amendment iShares Trust filed with the SEC. One tranche expires each month and a new one replaces it, so the positions roll across a calendar quarter.
Each tranche pairs two trades. The fund buys in-the-money calls struck near 90% of IBIT’s value, which sets the initial loss limit the filing labels the Floor. It then sells out-of-the-money calls to help pay for that protection, and their strike becomes the ceiling on gains.
A cash sleeve of Treasuries, money market funds and short-term investment-grade debt adds interest income to offset option costs. The fund won’t hold Bitcoin or any Bitcoin exchange-traded product directly. The filing names Erin Armstrong, Kyle McClements and Richard Mejzak as its portfolio managers.
🚨HUGE: BlackRock officially files for a Bitcoin ETF designed to LIMIT losses. The iShares Bitcoin Managed Protection ETF would offer upside on its $65 BILLION IBIT up to a cap while seeking "a level of downside protection," per its SEC filing. IBIT and BITA, BlackRock’s covered-call income fund, both remain exposed to Bitcoin’s drops. This one would buy and sell call options on IBIT and hold fixed income to help cushion losses. Its proposed ticker is PBIT.
— Coin Bureau (@coinbureau) October 19, 2026
Conditions Behind Prospectus
The protection comes with conditions. Fees sit outside the floor, and BlackRock keeps wide discretion to reset strike levels. A tranche’s potential loss also grows past the Floor once Bitcoin climbs after that tranche opens. With overlapping tranches, the fund promises no fixed floor or cap. The filing warns that “investors may lose some or all of their money.” It also classifies PBIT as non-diversified, meaning it can concentrate in a few counterparties.
Bloomberg Intelligence ETF analyst James Seyffart said PBIT is BlackRock’s third Bitcoin ETF filing. It follows IBIT and the iShares Bitcoin Premium Income ETF (BITA), which sells IBIT calls for income. The firm’s Bitcoin and Ethereum ETF lineup still covers no other crypto assets, he added.
Seyffart pointed to floor funds already trading from Calamos, First Trust and Innovator, including CBOJ, BFJA and QBF. Even so, he argued, “when BlackRock does something (particularly in this space), it tends to make a big splash.“
IBIT carried the day’s inflows alone
CoinLaw ETF Tracker data showed IBIT was the only U.S. spot Bitcoin ETF to post inflows that session. Fidelity’s Bitcoin fund lost $83.6 million, and Grayscale’s shed $54.9 million.
That single session wiped out the prior week’s $228.5 million of withdrawals, though the group remains about $90.5 million negative for October. IBIT now holds $66.37 billion in net assets, out of $105.46 billion across all U.S. spot Bitcoin funds.
Bitcoin changed hands near $82,900 on Tuesday morning, up more than 1%, while a separate market report put it at $81,500. Rising bond yields and slumping stocks have pressured the asset for weeks, and retail sentiment on Stocktwits sat in its extreme bearish band.
The timing reads as a test of demand for hedged exposure. BlackRock is pitching a floored, capped wrapper while retail mood sits near a low and fresh ETF cash is pooling in one fund. The filing also discloses a quieter benefit for the sponsor. Options written on IBIT may pull more assets into IBIT, which would indirectly lift fees paid to BlackRock affiliates.
PBIT would post its tranche caps, protection start values and weights on iShares.com, and those figures will shift every time a monthly tranche rolls. The amendment is set to take effect 75 days after filing. Its fee table still shows a blank where the management fee will go.
