ETF Creation and Redemption: How Authorized Participants Keep Prices Near NAV

The primary market is a separate market

An ETF share trades on an exchange all day. The same share can also be created or destroyed, but only in a separate market with different participants, different order sizes and a different price convention. The SEC’s final rule adopting Rule 6c-11 describes the distinction directly: unlike a mutual fund, an ETF “does not sell or redeem individual shares.” Instead, authorized participants “purchase and redeem ETF shares directly from the ETF in blocks called ‘creation units.’”

That sentence is the whole architecture. Everything else — the basket, the cash balancing amount, the arbitrage, the premium and discount — follows from the fact that the primary market is wholesale and the secondary market is retail.

Who the authorized participants are

Rule 6c-11(a)(1) defines an authorized participant as a member or participant of a clearing agency registered with the SEC that has a written agreement with the ETF or one of its service providers allowing it to place orders for the purchase and redemption of creation units.

The agreement is the gate. An AP can act as principal for its own account, and it can also act as agent for market makers, proprietary trading firms, hedge funds and other institutional investors, collecting a fee for processing their creation units. That agency business matters: the number of firms with the agreement can be small while the number of institutions able to reach the primary market through them is larger.

A retail brokerage account does not confer AP status. It gives you the secondary market, where the price is set by supply and demand against the fund’s published NAV.

What is in a creation unit

The AP delivers a basket of securities and other assets identified by the ETF that day, plus a cash balancing amount. In return it receives the creation unit of shares. The rule says the basket is generally representative of the ETF’s portfolio, and that the basket plus the cash amount is equal in value to the aggregate NAV of the shares in the unit.

Two details are easy to miss.

First, the basket need not be a pro-rata slice. The rule permits an ETF to substitute other securities or cash for some or all of its holdings, subject to its exemptive relief. A bond ETF may deliver a representative sample rather than every bond it holds; a fund in a market with delivery frictions may use cash in place of assets it cannot transfer efficiently.

Second, the cash balancing amount is not a fee. It is the residual that makes the values match. Transaction fees are separate, and the rule describes them as intended to defray operational processing and brokerage costs and to prevent shareholder dilution.

Cash creation, in-kind creation and the bitcoin case

An in-kind creation delivers the fund’s assets. A cash creation delivers cash, and the fund buys the assets. Both are permitted under the rule, and the difference changes who carries the execution risk.

The SEC’s order approving the first spot bitcoin ETP proposals is explicit about which model those products used. The order states that the proposals before the Commission “only contemplate cash creation and redemption by authorized participants,” and that in-kind creation and redemption processes, and their relative benefits or drawbacks, were outside the scope of the order.

For a cash-created fund, the AP does not need to source the underlying asset before creating. It delivers cash, receives shares, and the fund’s execution desk buys the asset. The AP’s risk is the gap between the price it pays for the shares and the price at which it can sell them, plus the fund’s execution. For an in-kind fund, the AP must source the basket, which is a different and often larger operational task.

The arbitrage, in order

The rule describes the mechanism in both directions.

When ETF shares trade at a discount, an AP can buy shares in the secondary market, accumulate enough for a creation unit, and redeem them with the fund for the more valuable basket. The AP’s buying supports the share price; selling the basket assets presses on their price. Both move the two values toward each other. When shares trade at a premium, the transactions reverse: the AP assembles the basket, creates shares and sells them.

The rule also notes that arbitrage can happen without creation or redemption at all. A market participant can short the ETF and buy the underlying, or the reverse, and wait for the prices to converge. That is a trading strategy, not the primary-market mechanism, and it does not require an AP agreement. It also cannot create or destroy shares, so it does not relieve a persistent capacity constraint.

A worked example: one creation unit

Take an ETF with a NAV of $100.00 per share and a creation unit of 50,000 shares. The unit’s aggregate NAV is:

• 50,000 × $100.00 = $5,000,000

Suppose the fund specifies a basket worth $4,997,500 and requires a cash balancing amount of $2,500. The two add to $5,000,000, which is the NAV of the unit.

Now suppose the shares trade at $100.25, a 0.25% premium. The AP creates one unit and sells the shares:

• sale proceeds = 50,000 × $100.25 = $5,012,500
• cost of basket and cash = $5,000,000
• gross gain = $12,500
• transaction fee, assumed at $500 for this example = $500
• net gain = $12,000, or 0.24% of the unit’s NAV

The same arithmetic runs in reverse at a discount. At $99.75, the AP buys 50,000 shares for $4,987,500, redeems them for a basket worth $5,000,000, and clears $12,500 before the fee.

The useful number is the break-even premium. If the fee is $500 and the AP’s other frictions — financing, hedging, settlement — cost $1,000, the round trip needs more than $1,500 of gross gap to be worth doing. On a $5,000,000 unit that is 0.03%. Below that, the AP declines, and the market price can sit inside a band around NAV without anyone being able to profit from closing it.

This is why a small premium is not automatically an anomaly. It is the price of the service, expressed as a gap.

Where the mechanism fails

Too few APs. The rule’s arbitrage assumes someone is willing to take the other side. If only a handful of firms have agreements, or if they step back during stress, the gap can widen. The SEC’s rule release notes the concern directly when discussing the number of authorized participants.

A basket that cannot be delivered. Settlement cycles, market closures, custody arrangements and assets that cannot be transferred in kind can slow creation or redemption. A cash-created fund avoids some delivery problems but adds the fund’s own execution.

A once-a-day NAV. Most funds calculate NAV once daily, typically at the close of the major U.S. exchanges. An order submitted before the pricing time receives that day’s price; an order after it receives the next day’s. A market that trades around the clock against a once-a-day NAV has hours in which the ETF price and the last NAV describe different moments.

Fees and minimum sizes. A transaction fee that is small relative to a $5,000,000 unit is large relative to a $50,000 order. The primary market is not a retail channel, and its economics are sized accordingly.

Operational limits. A fund can suspend creations or redemptions in defined circumstances. When it does, the arbitrage channel is closed and the secondary market has to price the fund without it.

What this means for a secondary-market buyer

You are not the AP. Your access to NAV is indirect: you buy or sell at the exchange price, and the AP’s willingness to create and redeem is what keeps that price near the fund’s assets. Three practical consequences follow.

First, the premium or discount is a cost you may pay at entry and recover at exit, not a return. The market price versus NAV guide covers how to read the quoted gap; this article covers the machinery that produces it.

Second, the fund’s tracking is a separate question from its premium. A fund can track its index closely and still trade at a small premium because the arbitrage band is wider than its tracking error. The tracking difference versus tracking error guide separates those two measurements.

Third, the wrapper matters. A fund that holds assets directly, a fund that holds them through a custodian, and a tokenised fund that records claims on a ledger all have different creation and redemption paths. The tokenised treasuries guide describes how the same arbitrage logic looks when the fund’s shares are tokens.

How these sources were checked

The mechanics in this article come from the SEC’s final rule adopting Rule 6c-11 (Release No. 33-10695), retrieved 2026-10-24: the definition of an authorized participant, the creation-unit and basket description, the cash balancing amount, the two arbitrage directions, the daily NAV convention and transaction fees. The cash-creation statement for the first spot bitcoin ETP proposals comes from the SEC’s order in Release No. 34-99306, retrieved 2026-10-24.

The worked example is arithmetic on figures stated in the article, not a report of any fund’s actual creation unit, basket or fee. Fund prospectuses set those values, and they differ by product.