SoftBank's Vision Fund markets itself to potential investments as offering a gateway to Japanese markets. Z Holdings completed a merger with internet business Yahoo Japan and chat app Line this month.

The turnaround in valuations at the $100 billion Vision Fund was underscored at Coupang's New York debut earlier this month. SoftBank holds a 37% stake in Coupang, which has a market cap of $75 billion.

(Reporting by Sam Nussey; editing by David Evans)