South Korea's Ministry of Finance announced a tax reform plan in its '2026 Tax Reform Plan' to prevent major shareholders from artificially suppressing stock prices before inheritance or gift transfers. The reform replaces the current 4-month average stock price valuation method with a system applying up to 6.5-year average prices for inheritance and gift tax calculations. The government designed the measure to block loopholes where controlling shareholders lowered tax burdens through short-term price manipulation, dual listings, or exchangeable bond (EB) issuances that damaged corporate value. The adopted plan narrows the scope and penalties compared to the original legislative proposal introduced by Democratic Party lawmaker Lee So-young, which would have applied an absolute PBR 0.8 threshold to 1,291 companies. South Korea's capital markets have faced persistent undervaluation issues, with 47.5% of listed companies trading below PBR 0.8 as of the reform announcement date.
Government Narrows Scope from 1,291 to 200 Target Companies
The financial investment industry reported that the reform targets companies meeting specific long-term low price-to-book ratio (PBR) criteria. Eligible companies must have PBR in the bottom 25% of their KOSPI sector or bottom 10% of their KOSDAQ sector for 12 out of the most recent 13 half-year periods. The reform also covers companies that conducted dual listings or issued exchangeable bonds within the past year and experienced stock price drops of 30% or more compared to their 3-year average.
Korea Exchange simulations showed approximately 120 companies meet the long-term low PBR requirements. Including dual-listing and EB issuance criteria, the government estimates roughly 200 companies fall under the new rules. This represents a significant reduction from the 1,291 companies trading below PBR 0.8, which would have been covered under the original legislative proposal.
The government will apply the higher value between 1.3 times the current valuation and the long-term average stock price as the inheritance and gift tax assessment base for qualifying companies.
Analysts Critique Continued Reliance on Stock Price Metrics
Um Su-jin, researcher at Hanwha Investment & Securities, stated that the reform's continued use of stock prices as the valuation basis limits its effectiveness. Um noted, "Whether you average stock prices over 4 months, 2 years, or 3 years, the 'newly suppressed market price' will likely continue to dominate as the company valuation measure." For companies with persistently low PBR over multiple years, extending the evaluation period will not significantly increase assessed values, according to Um's analysis.
The researcher explained that for long-term low PBR companies, the 30% markup on current valuation will likely produce the highest assessment among the available calculation methods. Um characterized the long-term average price options as "likely to serve merely as window dressing" for companies that have maintained low PBR for extended periods.
Lower Penalties Reduce Incentive for Corporate Behavior Change
Kang Jin-hyuk, researcher at Shinhan Investment Corp., analyzed that the government plan uses lower penalties compared to the original proposal. The legislative bill set PBR 0.8 as the valuation floor, creating a structure where extremely low PBR companies faced sharply higher tax assessments. The adopted government plan centers on a 30% markup and long-term average prices instead.
Kang stated, "It's difficult to distinguish between structural low PBR and intentional price suppression, and the low penalties, price-based standards, and extended evaluation periods could actually create incentives for chronic price suppression." The assessment suggests the reform may not achieve its intended deterrent effect.
Tax Authority Discretion Raises Predictability Concerns
Companies meeting the eligibility criteria must prove they did not artificially suppress stock prices. Firms unable to provide sufficient evidence face review by the National Tax Service's Valuation Review Committee, which determines both whether price manipulation occurred and the applicable inheritance/gift tax valuation method.
Um Su-jin questioned the administrative approach, stating, "With the 'PBR 0.8' standard removed, the possibility of sharply increased tax burdens has also significantly decreased—so why is the tax authority deciding on a case-by-case basis whether price suppression occurred and what the tax amount should be? It makes one tilt their head." The researcher noted that without specific review criteria, the reform could reduce tax predictability for companies.
Limited Impact on Long-Term Shareholder Return Policies
Jung Da-som, researcher at Korea Investment & Securities, assessed that the government plan may reduce incentives for artificial price suppression but fails to encourage proactive corporate actions. Jung stated, "While the government plan can contribute to reducing incentives to artificially suppress stock prices, its impact on capital markets is limited because it does not provide incentives to raise stock prices through active IR activities, shareholder returns, or efficient capital allocation."
The researcher explained that perpetually undervalued companies face the 30% markup, removing any incentive for price support. Jung noted that companies could avoid low PBR designation through temporary positive catalysts that raise prices during just 2 half-year periods within the 6.5-year evaluation window, rather than through fundamental improvements or enhanced shareholder communication. Jung concluded, "It's difficult to expect long-term corporate value enhancement activities" under the adopted framework.
FAQ
What valuation method did South Korea's government adopt for inheritance and gift taxes on stocks?
The Ministry of Finance's 2026 Tax Reform Plan replaces the current 4-month average stock price method with a system applying up to 6.5-year average stock prices. For qualifying low PBR companies, tax authorities will use the higher value between 1.3 times the current valuation and the long-term average price as the assessment base.
How many companies does South Korea's stock price manipulation tax reform target?
Korea Exchange simulations show approximately 120 companies meet the long-term low PBR criteria (bottom 25% KOSPI sector or bottom 10% KOSDAQ sector for 12 of 13 recent half-year periods). Including dual-listing and exchangeable bond issuance cases with 30%+ price drops, the government estimates roughly 200 companies fall under the reform, down from 1,291 companies trading below PBR 0.8 that would have been covered under the original legislative proposal.
Why do analysts question the effectiveness of South Korea's inheritance tax reform for stock valuation?
Researchers including Um Su-jin at Hanwha Investment & Securities and Jung Da-som at Korea Investment & Securities stated the reform's continued reliance on stock prices as the valuation basis limits its impact. For companies with persistently low PBR over multiple years, extending the evaluation period will not significantly raise assessed values, and the 30% penalty is insufficient to drive fundamental improvements in shareholder returns or capital allocation according to their analyses.
