FIS (FIS), in a partnership with bitcoin-focused tech partner NYDIG, introduces a solution that allows banks to offer their customers the ability to buy, sell and hold bitcoin (BTC-USD).Currently, consumers and corporations must open new accounts, often with unregulated entities, and go outside of traditional banking relationships to acquire bitcoin, FIS said.The new product uses FIS Digital One Mobile solution to provide bitcoin services through a digital interface, enabling the banks to drive fee income and attract and retain customers.In addition to the commercial agreement, FIS Ventures, the venture arm of FIS, made an investment in NYDIG for an undisclosed amount.Earlier (Feb. 17), NYDIG is one of the companies that has filed with the SEC to offer a bitcoin ETF.