TOKYO — In a move that may touch off a realignment in the cryptocurrency exchange business, Yahoo Japan next month will acquire 40% of operator BitARG Exchange Tokyo, then launch a full-blown exchange in April 2019 or later.

The Yahoo Japan exchange will be newly built but based on BitARG’s system.

Yahoo Japan will make additional investments in BitARG, which is registered with the Financial Services Agency, early in 2019.

The two companies have reported their capital tie-up plan to the FSA.

The purchase of BitARG shares will be made through Tokyo’s YJFX, a wholly owned Yahoo subsidiary that operates foreign exchange transaction services. YJFX will pay about 2 billion yen ($19 million) for a 40% stake in BitARG. The stake will be made up of outstanding shares and newly issued stock.

The additional investments will be made from January to March 2019 through another Yahoo group company.

Starting next month, YJFX executives and engineers will be dispatched to BitARG, where they will spend about a year developing the new exchange system. They will also work on a corporate governance structure, a customer management system and internal controls