ROUND LAB

The number in the flagship product's name is a date, not a SKU. "1025" marks October 25, the day in 1900 that Korea cites for its formal claim over the Dokdo islets, a cluster of rocks whose sovereignty Seoul and Tokyo still contest, and the line draws deep-sea water pulled from roughly five thousand feet near those rocks. It's an unusually political launch pad for a toner, and the brand has steered donations toward a school tied to the Dokdo cause.

The company behind it is Serin Company, the firm co-founded by Lee Yong-hak and Jung Seo-rin that built the brand from that single patriotic anchor outward. The Dokdo toner became a runaway bestseller, racking up tens of thousands of reviews on Korea's Hwahae app and topping toner sales for years, and that success transformed Serin into an acquisition target. In 2022 a stake changed hands for roughly 230 billion won; by December 2025 the company Goodai Global bought Serin outright for about 800 billion won, a more-than-threefold appreciation in three years that tracked the brand's climb from indie launch to one of K-beauty's most coveted assets.

The catalog grew into a tour of Korean source ingredients beyond the deep-sea narrative: a Birch Juice line built on sap from Inje, plus pine, mugwort, and soybean ranges, each leaning on a regional botanical story. Strip away the geopolitics and the mineral mythology, though, and the real engine is unglamorous. The toner is mildly acidic, fragrance-free, and forgiving, the exact profile reactive skin rewards with repeat purchases. The origin tale gives the brand a distinct identity, but loyalty was earned on tolerance and price, not on where the water was drawn.

Sources:[1][2]