Post-Market Study for Medical Devices in South Korea: Scope, Periods and Preparation

1. Key takeaways

South Korea has set a deferred, post-market study gate for devices whose pre-market evidence is incomplete, based on Article 8 of the Medical Devices Act. The system was originally named re-examination (재심사) and was renamed post-market study (시판 후 조사) in the amendment of August 17, 2021; the current text no longer uses the re-examination wording.

• Three categories listed in Article 8(1) apply: newly developed medical devices (item 1), orphan medical devices (item 2) and equivalent medical devices (item 3). The period is uniform across the three categories in law — a period determined by the Minister of Food and Drug Safety within the range of not less than 4 years and not more than 7 years after marketing. The widely circulated split of 4 years for newly developed and 6 years for orphan devices has no legal basis and is not used in this guide. Article 8(2) separately provides that the period may be set differently after deliberation by the committee.
• The point most relevant to companies: the post-market study obligation is performed by the licence holder, but the data sources sit with the Chinese manufacturer. This timing mismatch between the two is the main failure cause GRZAN observes in projects.

2. Legal basis

The following instruments govern the applicability, period and documentation of the post-market study.

Note: the period of the post-market study is a statutory range — not less than 4 years and not more than 7 years after marketing — with the specific period determined by the Minister of Food and Drug Safety within that range. The previously circulated split of 4 years for newly developed and 6 years for orphan devices has no legal basis and is not used here; the exact period for a given case follows what is stated in the approval notice or the system registration.

3. Expert insights

Insight 1: the post-market study exchanges pre-market uncertainty for post-market evidence.

The Korean authorities grant market access for newly developed devices on the premise that existing evidence does not yet cover long-term performance, and push part of the evidence-gathering duty to the post-market phase. Understanding this changes the direction of preparation: the goal is not to prove the product has no problems, but to show that every item on the uncertainty list set at approval has been answered. GRZAN recommends keeping the review comments and response records from the approval stage — that list is the table of contents for the post-market study dossier.

Insight 2: the range of not less than 4 years and not more than 7 years defines the starting window for data accumulation.

The statutory range is not less than 4 years and not more than 7 years after marketing, with the specific period determined by the Minister, and companies cannot prepare on their own assumption of 4 years. Taking the 4-year floor and deducting dossier assembly and internal review, roughly just over 3 years remain usable for collecting post-market use data; if 6 or 7 years is set, the requirements on data volume and follow-up depth rise accordingly. If a product only reaches stable sales in the second year after approval, the sample size will struggle to support conclusions. GRZAN’s practice is to start use-data registration as soon as approval is obtained and the first shipment arrives, confirm the determined period for the product once the approval notice is issued, and schedule milestones backwards from it, rather than starting late.

Insight 3: the data ownership mismatch is more troublesome than the data itself.

The applicant for the post-market study dossier is the licence holder, while clinical use, follow-up and adverse event source data sit mostly with the manufacturer and the end hospitals. If the agreement does not state data provision duties and time limits, the licence holder requesting data shortly before the deadline often cannot obtain complete data. GRZAN recommends a dedicated clause on cooperation in post-market research and post-market studies in the KLH agreement, with yearly delivery milestones set against the determined study period.

Insight 4: the consequences of non-performance go beyond a single administrative action.

A late or unperformed post-market study directly affects the continued validity of the item and may draw the authority’s attention to the licence holder’s other items. It differs from item renewal under Article 49 of the Medical Devices Act — the latter is a periodic qualification renewal (see the guide on item renewal, the 5-year validity period and the first concentrated expiry window), while the former is a one-off evidence closure, and the two cannot substitute for each other.

4. Practical recommendations

• Start the countdown on the day of approval. Taking the approval effective date as the baseline, schedule backwards the three milestones of dossier assembly, data consolidation and internal review, leaving room for at least one pre-review.
• Convert the uncertainty list from the review stage into the dossier contents. Extract the open questions from the approval-stage deficiency responses and map each one to a post-market data source, as described in the guide on class 3 and class 4 device approval.
• Secure the data sources at the agreement level. State the data provision duty, format and deadlines in both the KLH agreement and the distribution agreement, and assign responsibility for non-provision.
• Produce an annual interim summary. Do not compress all analysis into the final year; an annual interim summary turns final dossier assembly from writing into compilation.
• Watch for re-evaluation in parallel. The post-market study and the re-evaluation under Article 9 of the Medical Devices Act exist side by side, as described in the guide on the re-evaluation system; the evidence on the two tracks should share one data foundation wherever possible.

5. Verification checklist

• □ Whether the device is subject to the post-market study: check Article 8(1) of the Medical Devices Act against the approval notice; the device is classified into one of the three categories of newly developed, orphan or equivalent devices, or a written non-applicability determination exists.
• □ Post-market study period: verify that the determined period stated in the approval notice falls within the statutory range; it falls within the range of not less than 4 years and not more than 7 years, and the approval notice governs.
• □ Data collection plan: check the post-market use data registration form and its start date; registration began with the first shipment and there is no gap.
• □ Source of the dossier contents: verify whether they derive from the approval-stage uncertainty list; each open question is mapped with none omitted.
• □ Data provision duties: sample the KLH agreement and distribution agreement clauses; clear data provision duties and deadlines are stated.
• □ Annual interim summaries: check the interim summary records for each year; the annual summaries are complete and can support the final report.
• □ Separation from other tracks: check the milestones of the post-market study, re-evaluation and item renewal; the three timelines are not conflated and the milestones are entered in the compliance calendar.

Regulatory information verified as of October 29, 2026.

How GRZAN can help. GRZAN provides medical device and IVD registration, quality system, Korean licence holder and local testing support for the Republic of Korea. Our team manages adverse event reporting and recall coordination with MFDS, and supports post-market vigilance obligations. Business enquiries: info@grzanglobal.com