A Japanese court awarded damages Wednesday to a woman in her 30s, who broke up with her same-sex partner because of infidelity, recognizing their common-law partnership despite same-sex marriage not being legal in the country.

The Mooka branch of the Utsunomiya District Court in Tochigi Prefecture ordered the former partner to pay 1.1 million yen ($10,170) to the plaintiff, who was seeking damages of 6.3 million yen.

According to the suit, the plaintiff and defendant moved in together in 2010. After acquiring a marriage certificate in the United States in 2014, the couple held a wedding ceremony in Japan the following year.

[Getty/Kyodo]

Soon afterward, the defendant revealed her desire to raise a child with the plaintiff and was artificially inseminated after finding a sperm donor on a social networking site.

However, the relationship between the couple broke down in January 2017 following the revelation that the defendant had an affair with the sperm donor.

The defendant subsequently gave birth, while the sperm donor went on to have gender reassignment surgery, and is now recognized as a woman.

The plaintiff had earlier bought a house for the couple to raise the child in, and also paid for the defendant's artificial insemination.

The plaintiff argued same-sex partnerships should have the same legal protections that common-law marriages receive in Japan. Specifically, she said her relationship with the defendant deserved protection because the couple held a wedding ceremony and had been long-time domestic partners.

The defendant refuted the claim saying their relationship was not protected under Japanese law, which does not recognize same-sex marriages.

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