BlackRock has asked U.S. regulators to approve a new bitcoin exchange-traded fund built around a deliberate trade: it cushions part of bitcoin’s declines, and it pays for that cushion by giving up gains above a set ceiling. The registration, a Form 485APOS filed with the Securities and Exchange Commission on October 19, 2026, covers the iShares Bitcoin Managed Protection ETF under the ticker PBIT.
The fund’s stated objective is exposure to the iShares Bitcoin Trust ETF, known as IBIT, “up to an approximate limit,” paired with “a level of downside protection.” The wording is precise. PBIT does not invest directly in bitcoin or in bitcoin exchange-traded products, and the protection it offers is a level rather than a promise.
An options book, not a spot holding
The prospectus describes a “Bitcoin Managed Protection Strategy” built from call options rather than coins. The fund buys call options in three overlapping tranches on what it calls bitcoin reference assets, sells call options against those positions to offset their cost, and keeps the rest of the portfolio in fixed-income instruments that generate interest income. The sold calls are what impose the cap.
The tranches are staggered so that one expires and a new one begins each month across a calendar quarter. That rolling schedule is designed to keep the fund exposed across a range of expiry dates instead of betting on a single point in time. BlackRock says it generally expects to use flexible exchange options, known as FLEX options, which are cleared and guaranteed for settlement by the Options Clearing Corporation rather than negotiated directly with a counterparty.
Why the protection is never free
A call spread caps gains by construction. The fund buys a call at one strike and sells a call at a higher strike; if the reference price closes above the higher strike, the gain stops at the distance between the two strikes, minus the net premium paid. The premium collected on the sold call, together with interest from the bond sleeve, is what funds the downside cushion. Every dollar of protection is purchased by forfeiting upside above the sold strike.
The filing is explicit that this is not a defined-outcome or buffer product. It makes no promise to absorb the first portion of a decline and provides no principal protection. The cushion is described only as “a level,” one that shifts with interest rates and volatility, and the fund retains discretion to hold more or fewer tranches.
What the filing leaves open
BlackRock names Erin Armstrong, Kyle McClements and Richard Mejzak as the portfolio managers. The preliminary prospectus leaves the management fee blank, a placeholder that will matter to anyone weighing the wrapper against assembling the same spread directly. The filing also carries the standard caution that there can be no assurance the strategy will operate as intended and that investors may lose some or all of their money.
The product is aimed at the allocator who wants bitcoin exposure but must justify drawdown risk to a committee. Its appeal is structure and convenience: a wrapper that keeps the trade running continuously rather than a position an investor has to rebuild by hand. The cap is not a defect in the design; it is the mechanism that makes the protection possible at all.
Adapted from BlackRock Files Third Bitcoin ETF With Downside Protection and Capped Upside.