An authorized participant is a broker-dealer with a contractual arrangement with the ETF issuer giving it the right to create new shares or redeem existing ones in large blocks — typically called creation units. APs sit between the ETF’s primary market and its secondary market and serve two roles: they are the mechanism through which all new money actually enters or leaves the fund, and they are the arbitrage agent that keeps the ETF’s market price aligned with the underlying basket’s NAV.
In a creation, the AP delivers the underlying basket (cash, or in some structures the underlying crypto) to the issuer and receives a creation unit’s worth of new ETF shares, which it sells into the secondary market. In a redemption, the AP buys ETF shares in the secondary market, delivers them to the issuer, and receives the underlying basket back. Each round trip nets a thin spread — the AP’s incentive to keep arbitraging.
When the ETF trades rich to NAV, the create-and-sell trade is profitable, and APs do it until the premium collapses. When the ETF trades cheap, the buy-and-redeem trade is profitable, and APs run that until the discount closes. The result is the tight basis-point band that spot crypto ETFs typically trade in.
Creation and redemption activity by APs is what drives net flow. When dashboards report a $200M inflow into a Bitcoin ETF, that is $200M in AP-driven creations — not secondary-market volume. AP capacity is also why a sudden, persistent premium or discount is meaningful: it implies APs are not stepping in fast enough to arb the gap, which usually points to a hedge-cost or capital-allocation constraint on the AP side.