Celltrion (068270.KS), South Korea's largest biosimilar developer, said its workers launched a labor union on June 1 — the first in the company's history since founder Seo Jung-jin started it in 2002, according to Chosun Biz and The Korea Times. The move lands as a separate dispute at Samsung Biologics (207940.KS), the world's largest biologics contract manufacturer by capacity, drags on: its union, which staged the first strike in the company's history, has shifted to a work-to-rule campaign after failing to reach a deal, etnews and Maeil Business Newspaper reported. For the first time, organized labor now sits inside both of the companies that anchor Korea's biologics contract-manufacturing industry.
For a global drug buyer, the immediate question is not about wages — it is whether the medicines keep coming. Biologic drugs are made from living cells that are cultured and purified over weeks; if a production run is halted, the batch can spoil and be discarded, Chosun Biz noted. That makes labor stoppages unusually expensive at a CDMO (contract development and manufacturing organization). The Korea Herald reported that Samsung Biologics estimated a roughly ₩150 billion ($102 million) hit from an earlier partial walkout, and that a five-day general strike could cost ₩640 billion ($435 million) or more — about half of the company's first-quarter revenue of ₩1.26 trillion ($857 million). The company said some production stoppages were unavoidable because of supply delays in key materials, affecting drugs that include cancer and HIV treatments, per the same report.
A strike at the company with some of the industry's strongest retention
The friction is striking precisely because Samsung Biologics' published workforce metrics are among the sector's strongest. An ESG report posted to the company's website on May 29 put the 2025 employee turnover rate at 1.9%, a record low and the fourth straight annual decline from 4.5% in 2021, with average pay up 44% over four years, etnews and Maeil Business Newspaper reported from the document. Yet the union still walked out. Its demands, according to The Korea Herald, include a 14% average wage increase, a one-time cash payout of ₩30 million ($20,400) per worker and a bonus equal to 20% of operating profit; the company has countered with a 6.2% raise. The Korea Herald reported that some 2,800 of the union's roughly 4,000 members joined the action, out of about 5,400 employees.
The backdrop is a banner year for both firms. Samsung Biologics grew 2025 revenue 30.3% to about ₩4.55 trillion ($3.1 billion) and posted operating profit of ₩2.06 trillion ($1.4 billion) — the first time a Korean biopharma company has cleared the ₩2 trillion profit mark — helped by full utilization of its Plant 4, FiercePharma and The Korea Herald reported. Chosun Biz reported that securities analysts expect each company's consolidated revenue to reach the ₩5 trillion ($3.4 billion) range this year, and the unions argue that record results should be shared with staff. Celltrion's union, nicknamed "Unitrion," is demanding transparent profit-sharing criteria, a negotiation-based wage system, more permanent staff to meet GMP (good manufacturing practice) standards, an end to rotational shift assignments, and better welfare, per Chosun Biz. Celltrion said it respects the legally guaranteed right to organize and will respond in good faith.
What it signals and what to watch
The twin developments extend a trend that began outside biopharma: Samsung Group, long known for resisting organized labor, saw its first employee-led strike at Samsung Electronics in June 2024, per Al Jazeera. The arrival of unions at both leading Korean CDMOs raises a question their multinational clients will weigh — whether Korea's reputation for uninterrupted biologics supply holds. A bio-industry source told Chosun Biz that overseas pharma companies signing contracts will now scrutinize the risk of production interruptions more closely.
The near-term confirming signal is whether Samsung Biologics and its union reach a settlement before the work-to-rule action escalates back into a full walkout, and whether Celltrion's newly formed union files for collective bargaining. Both would test how much of this year's record profitability flows to a labor cost line that, until now, barely existed at either company.
This article is for informational purposes only and does not constitute investment advice. Figures are converted at approximately 1,470 won per U.S. dollar, the rate implied by the sources cited.
Sources
- https://www.koreaherald.com/article/10730324
- https://www.koreaherald.com/article/10730418
- https://www.koreatimes.co.kr/business/companies/20260601/workers-at-celltrion-launch-first-union-in-companys-history
- https://www.etnews.com/20260601000154
- https://www.mk.co.kr/news/it/12063067
- https://biz.chosun.com/science-chosun/bio/2026/06/01/BKA6PLXLD5CZPP5IXKJYVJWG54/
