Coupang Investors ISDS 2026 Lawsuit: U.S. Firms Challenge Seoul's Regulatory Enforcement

What started as a massive data leak has now escalated into a multi-billion dollar international legal showdown. According to Reuters, major U.S. investors in Coupang—Greenoaks and Altimeter—filed a notice of intent to pursue an Investor-State Dispute Settlement (ISDS) claim against the South Korean government on January 22, 2026. They're taking issue with Seoul's handling of a major data breach that hit the e-commerce giant late last year.

Coupang Investors ISDS 2026 Case: Allegations of Discriminatory Treatment

The investors claim that South Korea's aggressive probe into Coupang violated obligations under the Korea-U.S. FTA, specifically regarding fair and equitable treatment. The dispute stems from a November 2025 incident where personal data of roughly 34 million customers was leaked. While Seoul maintains its investigation is standard legal enforcement, the investors argue it’s a targeted campaign against the U.S.-listed firm that has caused billions of dollars in losses.

Yonhap reports that the two firms haven't stopped at arbitration. They've also asked the U.S. Trade Representative (USTR) to investigate and potentially impose tariffs or other sanctions. The Ministry of Justice in Seoul responded that they'll "actively respond" by forming a specialized team to review the legal merits of the claim.

Potential Impact on Korea-U.S. Trade Relations

Under the current rules, a formal arbitration can begin 90 days after the submission of the notice. This case is particularly sensitive as Coupang generates about 90% of its sales in Korea despite being founded by Korean-American entrepreneur Bom Kim. Cheong Wa Dae has cautioned against letting this spill over into a broader trade row, emphasizing the "unprecedented" scale of the data breach.