Bain Capital has confirmed that a special-purpose investment vehicle it established for SK Hynix still holds a 14% stake in Kioxia Holdings, the Japanese NAND flash memory giant formerly known as Toshiba Memory. The confirmation comes as Bain itself has fully exited its own position, capping what appears to be one of the most lucrative private equity trades in recent memory, with estimated profits of around $15 billion.
The anatomy of a $15 billion trade
In 2018, a Bain-led consortium acquired Toshiba’s memory operations for $18 billion. SK Hynix, the South Korean memory chip titan, was part of that consortium and picked up convertible bonds along with its stake through the Bain-created special-purpose vehicle.
Bain’s exit was methodical. The firm held roughly 44% of Kioxia as recently as December 2025. By mid-June 2026, that had been whittled down to approximately 14%. By early July, Bain Managing Partner David Gross confirmed the full divestment was complete.
What fueled it was timing and a structural shift in demand. Kioxia is Japan’s only major producer of NAND flash memory, the technology that powers solid-state drives and data-center storage. As AI workloads exploded, so did the need for high-performance storage. Kioxia’s public listing crystallized that valuation surge.
