STORY: South Korea will fine e-commerce giant Coupang just over $409 million.

It's over a massive leak of customer information last year.

It marks the country's largest data breach penalty on a company.

The Personal Information Protection Commission said Coupang had leaked personal data of more than 33 million customers.

And the firm failed to detect the breach within the 72 hours required by the law.

The privacy regulator further said the breach happened due to Coupang's - quote - ''lack of safety measures and systems, not sophisticated hacking".

Separately, the regulator found the company illegally collected information of around 11 million customers without their agreement.

The Seattle-based firm generates most of its revenue in South Korea.

Offering fast delivery of groceries, food and other goods.

The fine amounts to 1.4% of Coupang's revenue in 2025, according to Reuters' calculation.

Coupang apologized for having caused concern to the public and its customers.