Grayscale Investments further signaled its intent to turn its bitcoin fund (GBTC) into an exchange-traded fund (ETF) Tuesday when the crypto assets manager tapped BNY Mellon for a series of key backend roles.

Per the agreement, BNY Mellon will handle accounting and administrative services for GBTC starting in October. That relationship will eventually morph into transfer agent and ETF services provider for a converted GBTC ETF, a future the pair said “is anticipated” without giving a date.

The partnership is the latest sign that Grayscale is moving forward with converting its massive bitcoin trust product – at press time GBTC held $22 billion in assets – into a far more widely available ETF. Such a product would need the types of backend services that this deal locks in.

CoinDesk is owned by Grayscale parent company Digital Currency Group.

BNY Mellon, the world’s largest custodian bank, has a similar deal lined up for the proposed First Trust Skybridge Bitcoin ETF.

Getting a bitcoin ETF to the U.S. market is hardly assured, however.

Any product would need the blessing of the hyper-skeptical Securities and Exchange Commission. The U.S. markets regulator has never signed off on a bitcoin ETF application, though it had many opportunities to do so.

Grayscale Bitcoin Trust remains a popular crypto-exposure method on Wall Street despite its high fees and tendency to trade at premiums and discounts to its underlying bitcoin. It would face a stiff challenge from any bitcoin ETF that clears the regulatory bar.