The most dramatic delisting triggers and the most frequent ones are different
Over the past five years (2020–2024), audit opinion shortfalls accounted for 236 cases of delisting triggers, followed by embezzlement and breach of fiduciary duty with 71 cases, and unfaithful disclosure with 27 cases. The reality of delisting is less dramatic than commonly imagined — and far more structural. In that sense, audit opinion shortfalls should be viewed not as exceptional incidents but as an ever-present risk that listed companies must prepare for first.
Audit opinion shortfalls matter not simply because of their high frequency. This single trigger simultaneously causes prolonged delisting reviews, gaps in investor protection, underperforming companies lingering in the market, and erosion of market confidence. That is precisely why financial authorities singled out audit opinion shortfalls as a target for tighter standards in their 2025 delisting reform plan. Audit opinion shortfalls are not merely an accounting issue — they ultimately become a capital market governance problem.
Why a single line of audit opinion can shake a company
The delisting system triggered by audit opinion shortfalls cannot be accurately understood through the simple notion that "problems in an audit report lead to delisting." The actual system is a complex structure combining formal delisting triggers, substantive listing eligibility reviews, improvement periods, re-audits, subsequent audit opinions, designated auditors, and the recently introduced immediate delisting provisions. The evolution of this system should therefore be seen not as a simple history of regulatory tightening or easing, but as a process of recalibrating where in the delisting procedure remedial opportunities are cut off and where they are reopened.
The starting point was the regulatory tightening of 2002. Audit reports submitted by auditors of listed companies are virtually the only materials for assessing a listed company's financial soundness and accounting transparency, while also serving as a primary basis for investors' decision-making and a prerequisite for fair and reasonable market price formation. Therefore, when the auditor's opinion in an audit report is adverse or a disclaimer, the potential to undermine the confidence of the investing public can be considered objectively evident. The Korea Exchange (KRX) cited the background for the 2002 tightening as follows: after the foreign exchange crisis that began in late 1997, companies became heavily dependent on direct financing through the exchange market for fundraising, necessitating stricter delisting standards for investor protection. Accordingly, one of the delisting criteria under the Securities Listing Regulations — previously "adverse or disclaimer opinions for two consecutive fiscal years" — was tightened to "adverse or disclaimer opinion for the most recent fiscal year." For the KOSDAQ market, regulations were further strengthened so that companies receiving not only adverse or disclaimer opinions on their financial statements but also qualified opinions due to scope limitations would be immediately removed from the market.
The limits of formalism and the introduction of substantive review
From 2007 onward, multiple cases of embezzlement, breach of fiduciary duty, and accounting fraud emerged at some companies, while others began circumventing formal delisting criteria — such as capital impairment and non-clean audit opinions — through methods like obtaining reissued audit opinions. Financial authorities and the KRX concluded that the existing delisting system operated uniformly based on formal criteria and failed to adequately reflect companies' actual conditions and market circumstances. They announced the introduction of a substantive review system for companies subject to delisting. The result was the listing eligibility substantive review system introduced in 2009. The KRX describes this as a system designed for both the early removal of insolvent companies and the normalization support of companies capable of rehabilitation.
However, the 2009 introduction of substantive review did not immediately convert audit opinion shortfalls into a "substantive review-type trigger." Audit opinion shortfalls remained a formal delisting trigger that had to be resolved to maintain listing status, while the substantive review operated as a separate, parallel standard for listing maintenance.
KOSDAQ changed first
The substantive integration of audit opinion shortfalls with substantive review began on the KOSDAQ market. Under KOSDAQ listing regulations amended in late 2017 and effective from 2018, when a company resolved an audit opinion-related delisting trigger by submitting an audit report, that resolution itself could serve as grounds for a listing eligibility substantive review — with an exception for companies under court-ordered rehabilitation proceedings. According to a press release issued by the Financial Services Commission (FSC) in 2018 titled "Completion of KOSDAQ Market Listing Regulation Amendments to Reform Listing Requirements and Strengthen Soundness," the change of audit opinion "from non-clean to clean" was viewed as a signal with a high probability of listing eligibility concerns. This was the background for expanding the scope of substantive review.
In this manner, the KRX and financial authorities' approach to managing audit opinion shortfalls moved in a stricter direction — maintaining the rigor of formalistic elements while layering on substantive review.
2019: From mandatory re-audit to next-year audit opinion
Yet resolving audit opinion shortfalls was not something the KRX or financial authorities could directly control. As the Act on External Audit of Stock Companies was strengthened and auditor liability increased, auditors grew increasingly reluctant to change their opinions even upon re-audit. The realistic possibility of resolving the formal delisting trigger of audit opinion shortfalls had become extremely difficult.
The 2019 reform was built on this awareness. The FSC explained that under the previous system, a listed company receiving a non-clean audit opinion faced delisting without substantive review, with trading immediately suspended. To file an objection, the company had to enter into a re-audit contract with the same auditor and obtain a clean opinion within six months for KOSDAQ or one year for the KOSPI market. This structure placed an excessive burden on companies in practice. Of 50 companies receiving non-clean opinions between 2015 and 2018, 10 had their re-audit contracts rejected. Re-audit fees ran 2.5 times higher than regular audit fees, and even companies that underwent re-audits found it difficult to have their audit opinions changed.
The core of the 2019 reform was to break that bottleneck. Authorities no longer required re-audits as a mandatory institutional prerequisite for companies with non-clean opinions. Instead, the system was restructured so that resolution of the formal delisting trigger could also be assessed based on the next fiscal year's audit opinion issued by a newly designated auditor. At the same time, for KOSDAQ companies, even if the next year's audit opinion changed to clean, listing maintenance would be determined through a listing eligibility substantive review. While the mandatory re-audit requirement was eased, it became even clearer that companies needed to rebuild their foundations in accounting, internal controls, and audit evidence sufficiently to obtain a clean opinion by the next audit season.
2025: No more time
Yet the system shifted direction once again. Amendments taking effect in March 2025 allow formal delisting triggers and listing eligibility substantive review triggers occurring simultaneously to be processed in parallel rather than sequentially, ensuring procedures are no longer delayed.
Furthermore, the KOSPI market now includes "cases where substantive review is deemed necessary even after audit opinion shortfall triggers have been resolved" as grounds for substantive review. The KRX's KOSPI Disclosure and Listing Operations Manual explains that even when formal delisting triggers are resolved through reissued audit reports or subsequent clean audit reports, companies with a history of audit opinion shortfalls often have deficiencies in their management conditions or internal control systems. The basis for subjecting such companies to substantive review was introduced in March 2025. The approach of simply resolving formal delisting triggers is no longer sufficient — even for KOSPI-listed companies.
Amendments taking effect in July of the same year are even more direct. Financial authorities diagnosed that the existing system had been operating in a somewhat lenient manner — granting improvement opportunities until the audit opinion for the fiscal year after next — which prolonged reviews. Cases also emerged where underperforming companies deliberately exploited audit opinion shortfalls to avoid delisting on other grounds and delay reviews. Accordingly, a structure for immediate delisting upon two consecutive audit opinion shortfalls was introduced. In short, the current system preserves limited recovery opportunities for a one-time shortfall while no longer tolerating repeated shortfalls and prolonged delays.
