Another reason for keeping one’s own name cited in the suit is that the bureaucratic process of making the change is extremely costly—Aono, shown above, said he spent ¥3 million ($28,200) to change his name (link in Japanese) on his shares when he married.

In January, a newly appointed female judge on Japan’s Supreme Court publicly said that she has continued to use her maiden name after marriage when handing down judgments. Yuko Miyazaki, 66, is the first justice to use the rule since it was recently changed—lawyers are allowed to use their pre-marriage names for legal complaints and other documents, but judges have only been allowed to do so since September. Miyazaki said that one source of motivation for her to use her maiden name professionally was because her mentor at university found that once she took her husband’s surname, papers she wrote under her pre-marriage name were not being acknowledged as her research.

Despite the recent push to change Japan’s law on last names, Yamaura said she is “quite pessimistic” about the prospect for real change. While support in Japan is growing for the law to be changed, it’s still far from a majority view. A study released this month by Japan’s cabinet office (link in Japanese) showed that 42.5% of respondents aged 18 and above supported a revision to the law to allow married couples to keep their own names, up 7 percentage points from 2012. Those who were against it declined by the same margin to 29.3%. But the country remains under the firm control of the conservative Liberal Democratic Party, and the justice ministry has said (link in Japanese) that the levels of support for the change don’t warrant moving quickly to amend the law.

A previous challenge to the 19th-century provision, brought by five women on the grounds of gender discrimination the same year Yamaura married, ended in defeat the year she divorced. Japan’s top court ruled then that the family-name law would be upheld as it did not harm ”individual dignity and equality between men and women,” and because maiden names can still be used informally.

Yamamura however, strongly disagrees that there’s any semblance of gender equality in how the law plays out: “Through my research into changing names, I discovered that men and women have different rights in Japan. I want to voice my opinion, I want to protest, even if it means bearing serious inconveniences.” And even though men are allowed to take their wives’ names in Japan, in reality those who do so are seen “pejoratively” as “men who obey women,” she added.

Though Yamaura lamented the cost of her decision—on top of the financial cost of changing her name to Takahashi on credit cards and other official documents, she’s no longer entitled to certain tax benefits accorded to married couples, such as when inheriting her husband’s wealth after his death—she maintains it was the right one: “There’s no other way. It’s also unhappy to live as someone else.”

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