Ryuichi Isaka has spent more than $25 billion during the past few years to bolster an empire spanning 85,000 convenience stores, gasoline stations and retail outlets. But he wants more.

The chief executive officer of Seven & I Holdings believes that the formula behind the success of 7-Eleven — the Japanese version, that is — can be exported across the globe, potentially through acquisitions.

"If there’s an opportunity, we’d proactively consider M&A,” Isaka said.