Korea's Disclosure System Explained: Periodic, Ad-Hoc, and Material-Fact Filings

Same Word, "Disclosure" — Yet One Draws a Fine and Another Draws Prosecutors

Open the disclosure filed by a stock you hold, and sometimes it shows up on the Korea Exchange's listing-disclosure site (KIND); other times it shows up on the Financial Supervisory Service's electronic disclosure system (DART). One company files a day late and gets hit with "penalty points." Another company delays reporting something similar and ends up facing criminal referral. Investors tend to lump all of this under one word, "disclosure," but in practice several distinct systems sit behind that single word — different legal basis, different receiving authority, and very different consequences for missing a deadline. This lesson doesn't tell you how to read a disclosure as a buy or sell signal; that's a question for the strategy course. What it covers is why disclosure in Korea splits into several separate regimes in the first place, and why the distinction actually matters.

The Big Picture — Two Authorities, Two Legal Foundations

Korean corporate disclosure runs on two separate legal foundations. One is disclosure the Capital Markets Act itself directly requires, filed with the Financial Services Commission (administered day-to-day by the Financial Supervisory Service) and published through DART. The other is disclosure the Korea Exchange requires as a condition of the listing contract, governed not by statute but by the exchange's own disclosure regulations, and published through KIND. Periodic disclosure and material-fact reports (covered below) belong to the first category — statute-based. Ad-hoc disclosure and inquiry disclosure belong to the second — exchange-contract-based. This split matters for more than just which website to check: miss the same underlying fact, and the consequences differ in kind. A statutory violation can escalate to criminal penalties or administrative fines; a listing-contract violation is usually limited to contractual sanctions the exchange itself imposes, such as penalty points.

Periodic Disclosure — Fixed Cycle, Fixed Deadline

Periodic disclosure covers the reports every listed company files on a recurring schedule. Capital Markets Act Article 159 governs the annual business report; Article 160 governs the semi-annual and quarterly reports. The annual report is due within 90 days of fiscal year-end; the semi-annual and quarterly reports are due within 45 days of each period's end. Nearly every listed company must file. The CEO and the officer responsible for disclosure must personally confirm and sign that the report contains no material misstatement or omission. If an unavoidable delay occurs — commonly because the external auditor hasn't finished — the company can report that reason seven days before the deadline and receive up to a five-business-day extension. As of July 2025, newly listed companies must also disclose the quarter or half-year immediately preceding listing, closing a gap where a company's track record right before going public previously went unreported. Missing periodic disclosure can draw up to one year's imprisonment or a fine of up to 30 million won, plus a separate administrative fine — a far heavier statutory penalty than violating ad-hoc disclosure, covered next.

Ad-Hoc Disclosure — Whatever the Exchange Decides Needs Reporting, Whenever It Happens

Where periodic disclosure runs on a fixed cycle, ad-hoc disclosure (수시공시) requires reporting the moment something material happens. The key difference from periodic disclosure is its legal basis: not the Capital Markets Act, but the Korea Exchange's own disclosure regulations for the KOSPI or KOSDAQ market. The exchange lists specific triggering events in advance — signing or terminating a major contract, a lawsuit being filed, a CEO change, pursuing a merger — and requires disclosure whenever one occurs. Since a 2015 amendment, a catch-all clause also covers any fact "materially affecting the stock price or an investor's decision," even if it doesn't match an item on the enumerated list — giving the exchange a basis to demand disclosure for new kinds of material events the rulebook hasn't explicitly named yet. This category also includes voluntary disclosure (자율공시) — a company proactively clarifying a press report without being asked — and deferred disclosure, which lets a company delay releasing commercially sensitive information for a limited window. Violating ad-hoc disclosure rules draws penalty points and fines from the exchange itself, and enough accumulated points can trigger designation as a company with poor disclosure practices — serious, but a contractual sanction rather than a criminal one.

Material-Fact Reports — Why the Same Kind of "Big News" Sometimes Needs a Separate Statutory Filing

The filing most often confused with ad-hoc disclosure is the material-fact report (주요사항보고서). Both cover "something big happened at the company," but a material-fact report is a statutory duty under Capital Markets Act Article 161 and its enforcement decree Article 171, filed not with the exchange but directly with the Financial Services Commission. It covers events that threaten the company's continued existence or reshape its capital structure: default or suspension of current-account transactions, full or partial suspension of business operations, filing for court-led rehabilitation, grounds for dissolution, changes in capital, the transfer or acquisition of a major business or asset (generally 10% or more of total assets, per the enforcement decree), buying back or disposing of treasury stock, and decisions to issue convertible, exchangeable, or warrant-linked bonds. A January 2025 amendment widened the scope beyond capital changes to also cover liability changes — including contingent capital securities and bonds with maturity-extension features. The filing deadline generally runs to the day after the triggering fact occurs, with a few items allowed three days, and convertible or warrant-bond issuance decisions due by the earlier of the day after the decision or one week before the funds are due. Because this is a direct statutory obligation, violating it can draw criminal penalties or administrative fines well beyond what an ad-hoc disclosure violation carries. Notably, Korea's Supreme Court ruled in 2023 (case 2023Da271798) that "litigation" as a triggering event under this rule covers only securities-related lawsuits, not litigation generally — a reminder of how narrowly courts read the scope of a statutory disclosure duty.

A concrete number makes the threshold clearer. Say a company with 1 trillion won in total assets sells off a business unit worth 200 billion won — 20% of total assets, well past the enforcement decree's 10% threshold. That company must file a material-fact report with the Financial Services Commission by the day after the sale decision, and failing to do so means facing statutory liability, not just an exchange penalty point. If the same company instead sells a piece of equipment worth 5 billion won — just 0.5% of total assets — no material-fact filing is triggered at all; depending on the specifics, only ordinary ad-hoc disclosure might apply. The same action, "selling an asset," falls under an entirely different regime depending purely on whether it clears the legally defined size threshold.

Inquiry Disclosure — When the Exchange Asks First

Everything covered so far starts with the company reporting on its own initiative. Inquiry disclosure (조회공시) runs in reverse. When a stock's price or trading volume swings unusually, or a rumor about a merger or a new drug spreads through the market, the exchange proactively asks the listed company to confirm or deny it. The company must respond within a deadline the exchange sets case by case — commonly a specific time the next business day, though this varies by situation rather than following one fixed universal rule — and trading in the stock is frequently halted until that response is published. If the rumor turns out to be unfounded, trading resumes; if it turns out to be true, that confirmation often triggers a separate round of ad-hoc disclosure or even a material-fact report. Inquiry disclosure matters because it shows the system isn't purely one-directional — the exchange actively investigates whether information already circulating in the market is actually true. A well-documented illustration of why this matters: in 2010, a listed Korean company promoted a major overseas resource-development project, citing a foreign government announcement, and its stock surged — only for that underlying claim to later prove false, with the company's executives ultimately convicted of stock-price manipulation (the CNK International case). It's frequently cited less as a textbook inquiry-disclosure procedure and more as a cautionary example of what happens when unverified rumor or promotion gets priced into a stock before anyone checks it.

Where Fair Disclosure Fits — Outside This Lesson's Scope

One more piece belongs on this map: fair disclosure, the rule requiring a company that briefs analysts or institutional investors on material non-public information to release the same information to the entire market at the same time. It sits alongside periodic disclosure, ad-hoc disclosure, material-fact reports, and inquiry disclosure as another category of ongoing public disclosure, but its mechanics and its relationship to insider-trading rules are already covered in depth in What Is Insider Trading? — this lesson only places it on the overall map.

Why This Distinction Actually Matters for an Investor

Knowing these four categories apart clarifies two practical things. First, there's usually a sequence. A major event — a big contract, a merger — typically surfaces first through ad-hoc disclosure (or a response to an inquiry-disclosure request), and if it also clears a statutory threshold like the asset-size test above, a material-fact report follows through its own separate legal process. The same piece of news appearing to show up twice isn't duplication; it's two distinct legal obligations each running their own procedure. Second, understanding the difference in stakes prevents misreading severity: a headline about a company being designated for poor disclosure practices and a headline about a company facing prosecutorial scrutiny over a material-fact filing are not the same tier of problem — one is a breach of a listing contract, the other a breach of statute. Getting used to checking periodic disclosure for the slow, steady information (quarterly results, strategy) and the other three channels for sudden individual events makes it far easier to size up, at a glance, what kind of information any single filing on DART or KIND actually represents.

Takeaway

• Periodic disclosure (annual, semi-annual, quarterly reports) is a statutory duty under Capital Markets Act Articles 159-160: the annual report is due within 90 days, the semi-annual and quarterly reports within 45 days, filed with the Financial Services Commission.
• Ad-hoc disclosure runs on the Korea Exchange's own listing-contract rules, requiring disclosure whenever a material event occurs; a 2015 catch-all clause extends coverage beyond the explicitly listed trigger events.
• Material-fact reports are a separate statutory duty under Capital Markets Act Article 161, covering events that threaten a company's survival or reshape its capital/liability structure (default, rehabilitation filing, convertible bond issuance, and more), filed directly with the Financial Services Commission.
• Violating ad-hoc disclosure draws exchange penalty points, fines, and possible designation for poor disclosure practices; violating a material-fact report obligation can draw criminal penalties or administrative fines — a meaningfully heavier consequence.
• Inquiry disclosure is the exchange proactively asking a company to confirm or deny a market rumor or unusual price/volume move, with trading frequently halted until the company responds.

FAQ

Why do some disclosures appear on KIND but not on DART?

Ad-hoc and inquiry disclosures are based on Korea Exchange rules and are published through KIND first; only matters that also trigger a statutory filing obligation (like a material-fact report) get additionally filed on DART. Periodic disclosure and material-fact reports, by contrast, go through DART as their primary channel. Checking both systems gives a more complete picture of any single stock's disclosure history.

Is receiving an inquiry-disclosure request itself a bad sign?

Not necessarily. Inquiry disclosure is simply the exchange's procedure for confirming facts when a rumor circulates or price/volume behaves unusually — it doesn't presume any wrongdoing by the company. Many inquiry responses confirm the rumor was unfounded. What matters is the content of the response that follows, not the fact that a request was made.

If the same event gets disclosed twice, does that signal something is off?

It can happen that the same underlying event triggers both an ad-hoc disclosure and, separately, a material-fact report. That's not duplicate reporting — it reflects two distinct obligations (a listing-contract duty and a statutory duty) each following its own required procedure. When the timing and wording of both filings line up closely, it generally means one event got reported through two channels, each under its own legal basis.

⚠️ This article is for informational and educational purposes only and does not substitute for investment judgment or legal advice on any specific disclosure matter. Disclosure deadlines, procedures, and penalty levels can change with revisions to the Capital Markets Act and exchange disclosure regulations, so verify specifics against the original filings on DART and KIND, and consult a legal professional if needed.