June 1, 2018, is a day that will go down in Japanese labor law history. A single day saw two verdicts from two similar cases handed down by the Supreme Court, both based on the 2012 amendment to the Labor Contract Law.

The highest court in the land rarely rules on two cases on the same day, let alone two about the same issue, and on June 2, newspapers around the country — including the Yomiuri, Mainichi, Asahi, Sankei dailies and the Tokyo Shimbun — splashed them on their front pages.

Article 20 of Labor Contract Law prohibits irrational or unreasonable discrimination based on employment status, i.e., against those on fixed-term rather than permanent employment contracts.