The National Health Insurance Service has lost a lawsuit it filed against three tobacco companies to offset treatment costs for diseases linked to smoking.

The Seoul Central District Court on Friday ruled against the nation’s health insurer. 

The insurance agency filed the suit against KT&G Corporation and the local units of Philip Morris and British American Tobacco in April 2014, demanding the firms pay more than 50 billion won in damages. 

The amount is what the insurance service paid between 2003 and 2013 for patients suffering from three types of cancer related to smoking. These patients had smoked more than one packet of cigarettes every day for at least 20 years.