The part of the spot bitcoin ETF story I find genuinely interesting is buried in a section of the prospectus almost nobody reads, the one covering creation and redemption. When these funds launched, the SEC required them to run cash-only creates and redeems. Nearly every equity ETF you have ever owned runs on in-kind baskets instead. It reads like back-office trivia, but that one design choice decides who buys the bitcoin, who eats the execution slippage, how tight the spread on your screen can get, and in some scenarios what your tax bill looks like. So it is worth walking through both models properly.
The in-kind model, which is how ETFs normally breathe
An ETF does not grow or shrink by the fund itself buying and selling on the exchange. It grows and shrinks through authorized participants, a short list of large broker-dealers with an agreement to transact directly with the fund. When demand pushes the ETF price above the value of its holdings, an AP assembles the underlying basket of securities, hands the actual securities to the fund, and receives newly created ETF shares in return, typically in blocks of tens of thousands of shares. When the ETF trades below the value of its holdings, the AP runs it in reverse, returning shares and receiving the basket. That arbitrage keeps the market price pinned near net asset value, and competition between APs keeps the spread tight.
Two things about this design matter for our purposes. First, the AP bears the execution risk. If the basket moves against them while they assemble it, that is their problem, and they are about the best equipped firms on earth to hedge it. Second, in-kind redemption is the quiet reason ETFs are tax efficient in the US. When an AP redeems, the fund can hand over its lowest-cost-basis holdings without selling anything, so it never realizes the embedded gains that a mutual fund would eventually have to distribute to everyone still holding. Most of the ETF wrapper's reputation for tax efficiency traces back to this one mechanical detail.
Why the bitcoin funds launched cash-only
The SEC approved the spot bitcoin products on the condition that creation and redemption happen in cash. The reasoning, as far as anyone can reconstruct it, was about who is allowed to touch the asset. APs are registered broker-dealers, and regulators were not comfortable with broker-dealers taking custody of bitcoin, moving it on-chain, and absorbing the AML and custody questions that come with that. Cash creates confine the crypto handling to the trust, its custodian, and a small set of designated trading counterparties. The AP never holds a coin.
Mechanically it works like this. An AP that wants to create shares wires cash to the trust. The trust, through its trading agents, then goes out and buys the bitcoin, usually benchmarked to a reference rate struck around the equity market close. Here is the friction. Bitcoin trades around the clock on venues with very different depth, the ETF's accounting day ends at 4pm New York time, and the actual coin purchase lands somewhere in that gap. Someone has to absorb the difference between the price the creation was struck at and the price the coin was actually bought at. Issuers largely pass that execution variance back to the AP through the cash amounts, and the AP, being a rational business, prices the uncertainty into the quotes it shows the market.
The practical result is an arbitrage band that is wider than it needs to be. In calm markets the difference is small, roughly a few basis points of extra spread. In fast markets it grows, because the AP's hedging cost grows. It shows up most visibly around weekends. Bitcoin can move hard on a Saturday while the ETF sits frozen at Friday's close, and on Monday morning the fund has to find the new price through an arb mechanism that costs more to run than the one inside your S&P 500 fund. Premiums and discounts appear, and they get paid by whoever crosses the spread at the wrong moment.
What in-kind changes, and for whom
Regulators have since opened the door to in-kind creation and redemption for these products, which quietly reverses most of the above. An AP that can deliver bitcoin directly gets to source it wherever it is cheapest, on exchange, over the counter, or from its own inventory, and it can hedge with CME futures the whole time. Execution risk moves from a chain of agents back to the single party best equipped to manage it, and best incentivized to, since every basis point of slippage saved is AP profit. Tighter hedging means tighter quotes, so the spread and the premium and discount behavior should compress at the margin. Not dramatically on a quiet Tuesday, but meaningfully in exactly the fast tape where you were paying the most before.
The tax angle is subtler and, I think, underappreciated. The spot bitcoin funds are structured as grantor trusts, so for tax purposes you are treated as owning your slice of the bitcoin directly. When redemptions happen in cash, the trust has to sell coin to raise that cash, and gains from those sales flow through pro rata to the shareholders who stayed. During a period of steady inflows nobody notices, because there is barely any selling. In a sustained outflow period, cash redemptions can hand long-term holders taxable gains they never asked for. In-kind redemptions sidestep this, because delivering coin to a redeeming AP does not require selling it. If you plan to hold one of these funds for years, this is the structural detail I would care about most.
One caveat before you assume everything is fixed. In-kind being permitted is different from in-kind being live in the specific fund you own. Each trust has to amend its own procedures, and each AP has to decide it actually wants to handle coin, build the wallets and the compliance around them, and staff the desk. Some funds will run both models side by side for a long while. The only way to know is to check the issuer's documents rather than assuming the wrapper works the way equity ETFs taught you it does.
How I would actually use this
The expense ratio is the visible cost of an ETF and the creation mechanics are the invisible one, so the point of knowing any of this is to price the invisible part before you buy. A few habits cover most of it:
- Before buying a crypto ETF, check whether it supports in-kind creates and redeems. The issuer FAQ or a prospectus supplement will say, and it takes about five minutes.
- Look at the fund's published premium and discount history. A fund that regularly swings to premiums during rallies is telling you what its arbitrage actually costs.
- Use limit orders, and be suspicious of Monday opens after big weekend moves. The classic failure mode is a market order into a premium that mean-reverts by lunch, a cost that never appears on any fee disclosure.
- If you are a long-term holder, weight the grantor trust tax mechanics more heavily than a few basis points of expense ratio difference between competing funds.
- If you trade around flows, treat creations and redemptions as a signal in their own right. Large cash redemptions during outflows force real selling in the underlying market. In-kind redemptions may not.
I ended up caring about this because I watch spot ETF flows next to derivatives positioning on Blockcircle, and the flow numbers only make sense once you know what a creation actually forces someone to go do in the underlying market. A cash create is a scheduled, benchmarked bitcoin purchase by an agent of the trust. An in-kind create might involve no market impact at all, just coin moving from an AP's inventory into a custodian's vault. The headline flow number looks identical in both cases, and the footprint is completely different.
You can own bitcoin through an ETF perfectly happily under either model. What you pay to do it, and who stands between you and the asset while you do, are set by this plumbing, and the plumbing is documented. Reading it once is about the cheapest edge available in this product category.