Korea’s Ministry of Health and Welfare said Monday it will revise the National Pensions Act to mandate that divorcing couples divide their pensions based on the time actually spent together.

The present law says the annuity should be divided based on the legal marriage period, regardless of how long the couple lived together.

The revision came after the Constitutional Court ruled on December 29 that Article 64, Clause 1 of the National Pensions Act ― which states that when divorcing, pensions must be divided in half for the legal marriage period ― “violates property rights” and is against the Constitution.

Unless parliament comes up with an alternative before June 30, 2018, the split annuity regulation will be annulled, according to Chosun Ilbo.

The revision came after National Pension Service statistics showed that those eligible to claim a split annuity in Korea - who paid monthly pension fees for five years or longer and were aged over 61 ― increased from 4,600 in 2010 to nearly 20,000 in 2016. With those in their 40s and 50s having the highest divorce rate of 8-10 per cent of the population, the number of people claiming a split annuity in future is likely to skyrocket.

But the revised law is expected to cause a flurry of legal challenges because there is no standard to determine the difference between the time the couples spent together and the legal marriage period.

“We still need time to determine whether to use official dossiers or the judicature’s decisions in acknowledging the times spent in living separately or away from home,” a Ministry of Health and Welfare official said.

Divorce also has increased in Japan, where “posthumous divorce” is a new trend.

The custom refers to those ― mostly women - who, after their partners die, file for divorce so they can legally detach themselves from in-laws.

Legal relations with in-laws can be cleared with the submission of a letter of request to government offices, without agreement from the deceased spouse or his or her family. “Posthumous divorces” jumped from 1,770 in 2005 to 2,800 in 2015, according to KBS.

Japan’s anti-in-laws sentiment is not so different to Korea’s, where women have long been taken for granted in providing services and sacrifice freedom participating in family events for in-laws.

“Many women were lost in finding the true meaning of marriage amid years of wedlock with violent or nonchalant husbands and unpleasing in-laws,” the reports said.

“Through the symbolic act of ‘cutting off relations,’ they have embarked on an exploration in search of their egos.”

Meanwhile, some Korean celebrities are splitting relatively quickly after their marriages.

Actors Lee Chan and Lee Min-young separated in just 12 days, while actress Kim Chung decided to divorce in only 13 days.

Most stars filed for divorce in less than three years, all reasoning that their “characters did not match.”