Standard Chartered and Northern Trust are the latest large financial firms to join the collection of banks linked to London-based cryptocurrency trading platform Pure Digital.

Pure Digital, an institutional-grade platform for over-the-counter trading and clearing of digital currencies, announced Tuesday that it has conducted a live test trade of Northern Trust and Standard Chartered’s Zodia Custody product.

At launch, Pure Digital will be multi-custodial, with trading participants free to use their preferred digital currency custody services and manage risk through a smart custody routing mechanism, the firm said in a press release.

Earlier this year, Pure Digital announced that it was working with custody giants State Street and BNY Mellon. Adding Standard Chartered and Northern Trust, which plan to use Zodia Custody, takes the number of banks and financial institutions linked to Pure Digital to six, said the platform’s CEO, Lauren Kiley. The other two banks have yet to be identified.

Asked how many custodians the platform will likely link up with, Kiley said via email: “We are custodian agnostic, there is no limit as long as they are bank-grade.”

She said the platform is hoping to go live early next year.