The Japan Times, Sept. 8, 2004
NAHA, Okinawa Pref.--- Landowners' descendents who only allow men to receive government-paid rent for land requisitioned by the U.S. military are not violating the Constitution... presiding Judge Masahiko Kubota of the high court said, "The court cannot recognize that the traditional custom in the area, which distinguishes between the treatment of male and female descendants concerning [landlord association] membership, is offensive to public order and morals."

....only male descendants of the original landowners can become full members. Wives of the male members can receive money after their husbands die but their daughters are not allowed to become full members.