More than a decade after Korea’s National Health Insurance Service (NHIS) filed suit against major tobacco companies over the cost of treating cancer patients, the World Health Organization (WHO) has entered the fray, calling the case a global benchmark for corporate accountability and urging courts to act.

NHIS is seeking 53.3 billion won ($39 million) from KT&G, Philip Morris Korea, and British American Tobacco (BAT) Korea, arguing the companies should cover treatment costs for 3,465 patients diagnosed with lung or laryngeal cancer after decades of heavy smoking. 

The case is built on epidemiological evidence from Korea’s national screening program and the Korean Cancer Prevention Study, with the core argument that insurers -- not taxpayers -- should be paying for preventable illness.

The latest round of global support follows growing domestic pressure ahead of final arguments, which were scheduled for May 22.

As reported last month, the Korean Academy of Family Medicine publicly urged the appeals court to “make a wise decision,” arguing that tobacco companies knowingly downplayed the risks of smoking while targeting consumers with misleading marketing.

International backing has since accelerated. The WHO submitted an amicus brief last month, alongside a letter from the Secretariat of the Framework Convention on Tobacco Control.

At the NHIS Global Forum this week, Benn McGrady, who leads WHO’s legal and policy team on health promotion, called the lawsuit part of a “global momentum” and urged governments to hold tobacco firms to account.

Dr. Neil Schluger, dean of New York Medical College, described the science as “long settled.” Smokers, he said, are 25 times more likely to develop lung cancer and typically lose more than a decade of life. The link, he added, is no longer in question. What’s lacking is accountability.

Philippe Trudel, who led Quebec's landmark tobacco class‑action, says Korea’s NHIS is following a tested roadmap. In 2015, a Quebec court ordered Imperial Tobacco Canada, JTI‑Macdonald, and Rothmans Benson & Hedges to pay over 15  billion Canadian dollars (roughly $11 billion).

That decision was upheld by the Quebec Court of Appeal in March 2019. Trudel said that with data, public backing, and patience, NHIS “can get there.”

But for NHIS, the lawsuit is not only about liability. It is also about cost. In 2011, NHIS said smoking-related diseases accounted for 1.7 trillion won in healthcare spending, or roughly 3.7 percent of the national insurance budget. By 2021, that figure had risen to 3.5 trillion won, as the list of recognized smoking-linked conditions expanded from 35 to 45.

Despite those numbers, NHIS says tobacco companies contribute nothing to the health system. Smokers pay a 841-won health levy per pack, but the remainder falls on the broader insurance pool, leaving non-smokers to absorb the cost through higher premiums. Officials say the imbalance threatens both fairness and financial sustainability.

Since filing the suit, NHIS has helped accelerate tobacco control policy. Graphic warning labels, higher taxes, and public health campaigns reframing smoking as a societal burden have reshaped public perception.

One 2014 ad, which aired nationally, showed a middle-aged man suffering a stroke after years of smoking. It became a flashpoint in the country’s anti-smoking movement.