Ko Sung-hyun
In October 2016, BWF announced Shin Baek-cheol's retirement. Shin actually announced that he left the Korean national team before the Rio Olympic 2016, but he didn't confirm that he retired from badminton. After his retirement, Shin was no longer eligible to enter the BWF international ranking tournament until he turned 31 years of age, based on the regulations from the Badminton Korea Association. Shin and his partner Ko Sung-hyun then made an injunction to the Seoul high courts by rejecting the BKA regulations. In May 2018, Shin and Ko finally got a chance to compete in the international tournament, after won their one-year legal battle against BKA.