SK Hynix nets 7 trillion won as Bain exits Kioxia in record deal

Bain Capital cashed out about 2.5 trillion yen ($17 billion) from Kioxia Holdings over the past year, the largest private equity exit in Japanese history, leaving SK Hynix as the NAND flash maker's de facto second-largest shareholder through a convertible bond structure that now faces antitrust scrutiny in Tokyo.

"Due to the competitive relationship, there is a possibility that SK Hynix's exercise of voting rights may differ from the interests of general shareholders," Kioxia said in a June filing, flagging the conflict to its investors.

SK Hynix invested 395 billion yen in 2018, splitting the capital between two special purpose companies — 266 billion yen in an SPC structured for share sales and 129 billion yen in one targeting governance participation. The first SPC was fully liquidated alongside Bain's exit, generating about 750 billion yen (7 trillion won) in proceeds for the Korean chipmaker, according to Meritz Securities. Toshiba, which reduced its stake to 15% from about 40%, realized roughly 800 billion yen from share sales.

The remaining SPC holds about 14% of Kioxia, and SK Hynix owns convertible bonds that could convert into that equity. But conversion requires antitrust clearance in multiple jurisdictions, and Japan's government is expected to scrutinize any transfer of control over a domestic semiconductor champion to a foreign competitor. SK Hynix has pledged not to exceed 15% voting rights through 2028, yet even that ceiling may prove difficult to reach if Tokyo blocks the conversion.

Bain's Record Exit Reshapes Kioxia's Ownership

Bain Capital acquired Toshiba Memory — renamed Kioxia — in 2018 through four SPCs that included investments from Apple, Dell, and SK Hynix. At the time of Kioxia's listing on the Tokyo Stock Exchange in December 2024, those SPCs held about 55% of shares, making Bain the largest shareholder. Over roughly 12 months, Bain sold all shares held by three of the four SPCs as Kioxia's stock price rose, generating proceeds that include profits for Apple, Dell, and SK Hynix's 266 billion yen contribution.

Toshiba, which had reinvested about 40% at the time of the acquisition, has now cut its holding to 15%, earning roughly double its initial investment. If Toshiba exits its remaining stake entirely, SK Hynix could become Kioxia's largest shareholder after converting its bonds — though the 2028 voting cap would limit its influence.

Antitrust and National Security Hurdles

SK Hynix and Kioxia are direct competitors in the NAND flash memory market, where SK Hynix holds about 20% of global share. Kioxia's June filing explicitly warned that the Korean company's voting rights could conflict with other shareholders' interests. Japanese policymakers are also expected to closely monitor any ownership change involving one of the country's key semiconductor companies.

Kioxia disclosed that while SK Hynix has not yet converted its bonds, it may have already begun regulatory procedures under antitrust, foreign exchange, and foreign transaction laws in multiple countries. SK Group insiders have expressed concern that converting the bonds may prove difficult in practice, according to the source material.

Meritz Securities estimates SK Hynix will book about 40 trillion won in cumulative investment gains in the second quarter of 2026, including both the SPC1 liquidation and SPC2 valuation gains, pushing pretax profit to roughly 100 trillion won. The windfall comes as SK Group chairman Chey Tae-won faces increased dividend demands from his divorce proceedings, raising the likelihood that SK Hynix will boost payouts to its parent company, SK Square.

SK Hynix shares, which trade on the Korea Exchange, could see a significant one-time earnings boost from the Kioxia gains, though the regulatory overhang around the convertible bond conversion introduces uncertainty. The NAND flash sector faces potential consolidation risk if SK Hynix eventually gains voting control, which would concentrate about a third of global NAND supply under a single corporate umbrella alongside Samsung Electronics, the market leader.

This article is for informational purposes only and does not constitute investment advice.