TITLE:
Shareholder Activism in a Concentrated Ownership Market: The Timing and Distribution of Value in Korea’s Post-2022 Wave
AUTHORS:
Aiden Donghoon Lee
KEYWORDS:
Shareholder Activism, Corporate Governance, Event Study, Korea Discount, Minority Shareholders
JOURNAL NAME:
Open Journal of Business and Management,
Vol.14 No.6,
November
2,
2026
ABSTRACT: Shareholder activism is often viewed as a mechanism for correcting governance failures and creating shareholder value. Yet much of the evidence supporting this view comes from markets with dispersed ownership, where activists primarily discipline managers. Less is known about whether activism creates lasting value in concentrated ownership systems, where conflicts arise between controlling and minority shareholders. Korea provides a timely setting. Since 2022, activist funds and retail investor coalitions have driven a rapid expansion of campaigns against family-controlled corporate groups, a wave widely described as a democratization of corporate governance and a remedy for the persistent “Korea Discount”. The distributional consequences of that wave have received little empirical scrutiny. This study examines twenty-one verifiable activist campaigns against Korean listed firms between 2022 and 2025, asking when value is created and whether it persists beyond the market’s initial response. Campaign announcements generate a significant positive market reaction, with a mean cumulative abnormal return of 6.96 percent over the [−5, +5] window. That premium, however, is front-loaded. Among campaigns with resolved governance outcomes and sufficient follow-up data, there is no statistically reliable evidence of sustained positive abnormal returns twelve months later, and the pattern is asymmetric; successful campaigns fail to show lasting gains, while the two campaigns that failed outright suffer sharply negative long-horizon returns. The findings distinguish the market’s expectation of governance improvement from evidence of lasting value creation. They also carry a distributional implication for a movement celebrated as empowering minority shareholders. Whether activism creates value and who captures that value are therefore different questions, and in concentrated ownership markets the second may mark the structural limit of what activism alone delivers.