SEOUL, Sept. 4 (UPI) — Just one day after President Lee Jae Myung’s cabinet approved the so-called “Yellow Envelope Law” on Tuesday, Hyundai Motors’ union launched its first partial strike in seven years, demanding the company notify labor in advance of new business ventures and overseas plant expansions, The Korea Economic Daily reported.

The law, passed by the National Assembly on Aug. 24 and set to take effect in early 2026, expands the scope of legal strikes to include management decisions such as mergers, restructuring and plant relocations.

It also limits corporate damage claims against unions. Analysts say the Hyundai union’s push reflects the law’s immediate influence on labor tactics.

Hyundai shut down assembly lines Wednesday in Ulsan, Jeonju and Asan for four hours, affecting an estimated 1,500 vehicles, Maeil Daily reported. GM Korea and HD Hyundai shipbuilding unions also staged partial walkouts to protest restructuring moves.

Observers warn the law, intended to protect workers from excessive corporate lawsuits, could embolden unions to intervene in management strategy, heightening labor unrest across Korea’s key industries, Maeil Business Newspaper reported.