Why is Japan adopting adult men?

By Sachiko Ishikawa  |  Translated by Hatsune Sawada

Japan boasts of having one of the highest adoption rates in the world, yet many who are unaware of its intricacies, will often assume the adoptees to be children, despite the reality being completely different—and one that often shocks non-Japanese people. The truth is that most families who adopt today in Japan choose to welcome adult men into their families, which is just one piece of evidence of the deeply patriarchal system in this country. And in the era of metoo and growing feminist movements in Japan, it is one more battle that needs to be tackled and won. Here at Voice Up Japan, we’ve done some research into the subject and here are our findings along with their sources.

The Economist (“Adult adoption in Japan: Keeping it in the family”) reported that, in 2011, more than 81,000 people were adopted in Japan. And that over 90% of them were of adult men in their 20s and 30s. Freakonomics takes it one step further in their 2011 article (“Why Adult Adoption is Key to the Success of Japanese Family Firms”) that stated that 98% were adult adoptions of men between the ages of 25 and 30.

Adult adoption is not a new phenomenon in Japanese culture. According to an article on Unseen Japan, in fact, it began as far back as the 13th century, where Kyoto’s Jōdo bukkyō (浄土仏教) Buddhist sect encouraged adult adoption in order to maintain their patriarchal system. However, it became a staple in society during the Edo Period. If they only had daughters, samurai families would adopt sons of other families of similar rank in order to preserve their surnames for prosperity, while the family who “gave away” their sons would rest assured that, as a new head of a household, they would be exempt from joining the military service.

Nowadays, however, with the advancement of technology and society, this tradition remains—if not unchanged, updated in its own particular way.

Business and corporations in Japan have always upheld a glass ceiling, and nothing proves this to be true more than the centuries-old tradition of adopting adult men for them to carry over family surnames and take over family businesses (from a small medical clinic in Fukuyama in this France 24 documentary to multinational empires like Suzuki Motor Corporation, whose current CEO Osamu Suzuki is the fourth adopted son to run it). This process of adoption is straightforward—leave behind their family name and be stricken from their koseki (family registry) in exchange for a new name, loyalty, and the privileges of being taken in with the same rights as a biological son. This includes the right to inheritance and carrying over the family business. The only stipulation is that the adoptive party needs to be older than the adoptee.

It is also common for these established families to adopt a suitable son-in-law (婿養子, mukoyoshi, in Japanese); therefore adopting as a son the husband of their daughters. One of the many benefits of this practice are tax deductions, as they increase with the number of heirs—therefore it’s “cheaper” to inherit assets the more heirs there are. In fact, in 1988, the Government had to place legal restrictions on the number of adoptions per heir allowed (two if the adopting family didn’t have any biological children, and one if they had any children at all) in order to stop families from abusing the system as a form of tax evasion.

Note: Surprisingly, even the Supreme Court is aware of this practice. In 2013, it rejected a suit brought forth by two daughters who claimed that their father had adopted their brother’s son, in his 20s, as a fourth heir. Despite the daughters’ claims that he had done so to lower his inheritance tax bill, the Court ruled that, even if he had done so for tax purposes, there was nothing wrong with that.

In a country where only 4.1% of married women keep their family surname (and separate surnames aren’t allowed by law), and with the fear that one’s name might be forgotten down the line, it’s easy to understand why adopting adult men, a practice done for centuries, seems like an easier solution than to change the current system as a whole. Unfortunately, recent data also shows that education is partial to men, so much so that in order to receive the same academic opportunities, women must work harder than their male peers, which translates into scandals such as the Tokyo Medical University who rigged the results of their female students claiming they would eventually leave their profession after marriage and childbirth. When a system is placed in order to make women fail despite their best efforts, it’s easier to arrange it so that men can continue to thrive at their expense.

And, to make matters worse, there are social theories that point to the low birth-rate as a culprit to this situation, claiming that, since the lack of children is to blame for the aging population, there are not enough people to carry on these family businesses. Many are quick to place the responsibility of the population issue onto women alone, claiming that their long working hours and lack of interest are to blame, rather than a system that has made it so that women remain invisible in a world ruled by and ruled for men.


Many Adoptions in Japan are Not About Raising Children

Keeping it in the family

Why Adult Adoption is Key to the Success of Japanese Family Firms

Why Do Adult Adoptions Abound in Japan’s Business World?

Adult men dominate Japan’s adoption market

Japanese companies — the (adopted) son rises

Resorting to adoption to avoid inheritance tax

Same surnames: Not a personal choice for all spouses

Girls still need higher entrance exam scores than boys at 80% of Tokyo high schools

Japan medical schools ‘rigged women’s results’

98% of all Japanese adoptions are employers adopting the adult men on their staff, not children

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