Analysis3 min read
BlackRock is in the news for two connected reasons. On 19 October it filed with the US Securities and Exchange Commission for the iShares Bitcoin Managed Protection ETF, which would trade under the ticker PBIT (Bitcoin.com). On the same day, its existing iShares Bitcoin Trust ETF recorded its largest daily net inflow in a year, $665.16 million according to SoSoValue data (The Block).
Taken together they describe a change in what BlackRock offers. It has been the largest distributor of direct bitcoin exposure through IBIT; the new filing is an attempt to offer bitcoin exposure with a different risk profile on top of it.
What the filing proposes
The fund would not hold bitcoin or bitcoin exchange-traded products directly. It would use options contracts and fixed-income securities to pursue gains linked to IBIT while seeking a level of downside protection (Bitcoin.com). In the filing BlackRock said the fund seeks upside exposure to IBIT or similar bitcoin exposure up to an approximate limit while seeking downside protection (Coin360).
The structure uses three overlapping sets of options, known as tranches, starting in different months. Each tranche buys call options with strike prices approximately 10 percent below the reference asset's value at the time the position is opened and sells calls above, which funds the protection and caps participation above that level. The prospectus anticipates using Flexible Exchange Options, and the fund would also hold cash, money market funds, short-term government obligations and investment-grade fixed-income securities, with interest income partly offsetting option costs (Bitcoin.com).
Two caveats matter for anyone reading the 10 percent figure. It is an initial threshold for each tranche before expenses, not a guaranteed maximum loss for shareholders, and BlackRock states that the strategy does not ensure protection against losses (FinanceFeeds). Selling calls also means the fund would underperform bitcoin in a rising market.
The filing is a post-effective amendment to an existing iShares Trust registration statement, and it proposes that the registration become effective 75 days after 19 October. The preliminary prospectus prohibits sales until the registration becomes effective. BlackRock Fund Advisors would manage the fund, which under its 80 percent investment policy would normally allocate at least 80 percent of net assets to bitcoin exposure or the protection strategy. The management fee is not yet specified, and the filing flags options liquidity, interest rate and counterparty risk (Bitcoin.com). A registration statement is not approval to trade (FinanceFeeds).
The flow behind the filing
On 19 October US spot bitcoin ETFs took in $526.6 million net, their biggest single-day haul since 22 September, with IBIT taking $665.2 million on its own. Fidelity's FBTC lost $83.6 million and Grayscale's GBTC lost $54.9 million, and IBIT was the only fund with a positive flow that day (CryptoBriefing). Trading volume across the spot bitcoin ETFs reached $2.09 billion, and cumulative net inflows since launch in January 2024 stand at $57.40 billion (CryptoBriefing). IBIT's share of inflows year to date is about 60 percent (CryptoETF.today).
From tokenized issuance to tokenized plumbing
On 19 October Bloomberg reported that BlackRock sees tokenized assets moving into the plumbing of traditional finance, not just existing on-chain. Dan Maley, who oversees BlackRock's cash business in Asia Pacific, said the firm's tokenized funds are already used as collateral in digital asset markets and that the larger unlock is use in the traditional financial ecosystem (Moneycontrol). Nikhil Sharma, on BlackRock's digital-assets team, said the earliest users were investors holding stablecoins on-chain who wanted yield (Moneycontrol).
BlackRock's first tokenized money market fund, BUIDL, has grown to about $2.3 billion since its 2024 launch, and shares of it are accepted as off-exchange collateral on Binance under an arrangement announced in November 2025 (TokenPost). BlackRock launched tokenized share classes for selected European money market funds on 4 August, using Kinexys by J.P. Morgan on Ethereum, and in September received approval for a Hong Kong dollar digital liquidity fund (TokenPost).
The obstacles are not technical. ISDA chief executive Scott O'Malia said questions on custody and segregation frameworks, capital and margin treatment, cross-border recognition and legal certainty must be addressed with industry standards and regulatory clarity (Moneycontrol). ISDA published a paper on documentation and operational questions for tokenized money market fund collateral on 6 October (TokenPost).
What to watch
The post-effective amendment proposes that PBIT become effective 75 days after 19 October 2026, and sales are prohibited until it does. Whether the fee is disclosed and how much of the European tokenized share class is actually pledged as collateral. And the daily flow data, where one fund has been carrying the category.
