SEOUL (Reuters) - Samsung Electronics Co Ltd 005930.KS board Chairman Lee Sang-hoon was sentenced to 1-1/2 years jail on Tuesday for sabotaging legitimate union activities, a South Korean court said.

Lee and about 25 other defendants were charged with sabotaging union activities by subcontracted workers at Samsung Electronics’ repair unit, Samsung Electronics Service Co Ltd.

When union activities took place at Samsung Electronics Service in 2013, Samsung Group’s now-defunct elite strategy office developed and implemented strategies to hinder the union’s operation, Seoul Central District Court ruled.

Samsung executives and employees were, to different degrees, involved in finding out sensitive information about union members to convince them to leave the union, inducing the closure of subcontracting firms with active unions and delaying negotiations between labor and management.

The verdict follows last week's ruling by the same court that gave a 16-month jail term to Samsung Electronics Vice-President Kang Kyung-hoon on charges of union-busting activities at now-defunct affiliate Samsung Everland, an amusement park operator and part of Samsung C&T 028260.KS.

“We humbly accept that the companies’ understanding and view towards labor unions in the past fell short of society’s expectations,” Samsung Electronics and Samsung C&T said.

A professor at Seoul National University, Park Sang-in, described the verdicts as “a further signal of change for South Korean judicial system, which previously gave lenient sentences to convicted businessmen”.

Samsung’s new leader, Jay Y. Lee, needs to “build industrial relations which are in line with global standards”, the professor added.

Lee himself is embroiled in separate trials in a corruption scandal involving former South Korean President Park Geun-hye.