Japan’s supreme court has struck down a law requiring transgender individuals to undergo surgical sterilisation before legally changing their gender. The 2003 law mandated the surgical removal of the ovaries or testes before a person could change gender. The court unanimously ruled this was a violation of the individual right of “pursuit of happiness” enshrined in the Japanese constitution, following a case filed by an anonymous transgender plaintiff who wished to change her gender to female on the family register without undergoing surgery. Japan is one of 39 countries requiring surgery for legal gender change, along with Iran, China and Egypt. In Japan, the opposition to liberalising gender identification laws is driven more by social conservatism than religious influence – the law has previously been defended in court on the grounds of preventing “social confusion” if, for example, a trans man became pregnant. But legal gender change still currently requires surgery, if not sterilisation.