A Seoul court rejected a landmark lawsuit by a same-sex couple over shared health insurance benefits Friday, a ruling that advocates say highlights the challenges the lesbian, gay, bisexual and transgender community faces in pursuing equal rights in South Korea. The suit was filed last year by So Seong-wook against South Korea’s National Health Insurance Service after it withdrew his ability to receive spousal benefits under the employer of his longtime partner, Kim Yong-min. South Korea does not recognize marriage or civil unions for same-sex couples, and the Seoul Administrative Court said Friday that it had no legal basis to expand the definition of marriage. “The union of a man and woman is still considered the fundamental element of marriage, according to civil law, precedents of the Supreme Court and the Constitutional Court and the general perception of society,” the judgment said. “Under the current legal system, it is difficult to evaluate the relationship between two people of the same sex as a common-law relationship,” it continued. The plaintiffs had argued that the NHIS recognizes non-married couples such as common-law spouses. They said after the ruling that they would appeal the decision.