An interested party or examiner may file a request with the Trademark Office to invalidate a registered trademark for violation of the provisions of the first paragraph of Article 23 or the fourth paragraph of Article 59.
Where a trademark has infringed another’s copyright, patent or other rights before its registration and a final court decision has been rendered confirming such infringement after registration of the trademark, the provisions of the preceding paragraph shall apply.

No invalidation proceedings against a registered trademark for violation of the provisions of Items 1, 2, 12 through 17, the first paragraph of Article 23 or the fourth paragraph of Article 59, may be instituted if five years have elapsed since the date of registration announcement.
Where five years have elapsed since the date of the final court decision as referred to in the second paragraph of the preceding Article, no invalidation proceedings shall be instituted.

Where the violation of Item 12, the first paragraph of Article 23 is in bad faith, the time limit prescribed in the first paragraph shall not apply.

Trademark invalidation proceedings shall be reviewed according to the Trademark Law effective at the time of registration announcement of the trademark at issue.

The Commissioner of the Trademark Office shall appoint three or more examiners to form a panel for review of invalidation proceedings.

Whenever, upon review, invalidation proceedings are rendered well-grounded, the challenged registration shall be cancelled. However, where the cause for invalidation has ceased to exist at the time the decision is rendered, the invalidation proceedings may be dismissed after taking into account the public interest and the interest of the parties concerned.

After a final decision has been rendered on invalidation proceedings, no further invalidation proceedings against the same trademark may be instituted by any person on the basis of the same facts, evidence and reasons.

The provisions of the second and third paragraphs of Article 40, the first and second paragraphs of Article 41, Articles 42 through 45, Article 47 and Article 49 shall apply mutatis mutandis to trademark invalidation proceedings.

Subsequent to registration of a trademark, the Trademark Office may, ex officio or upon request, cancel the registration in the event of any of the following circumstances:
1. whenever the trademark, to which unauthorized alterations or on which additional markings have been made thereby causing it to be identical with or similar to a trademark registered by another person, is used on the same or related goods or services as those upon which such registered trademark of another person is used thus likely to engender confusion among the related consumers;

2. whenever, without justifiable cause, the trademark is not used for three years or whenever, after a period of use, use of the trademark is discontinued for a term in excess of three successive years. This provision shall, however, not apply, if the trademark has been used by a licensee/sublicensee;

3. where the trademark proprietor fails to affix appropriate indication to distinguish its own goods or services as prescribed in Article 36. This provision shall, however, not apply, if such indication has been made thereby excluding the likelihood of confusion before a decision is rendered by the Trademark Office;

4. where the trademark has become a common symbol, name or shape of the designated goods or services;

5. where actual use of the trademark is likely to mislead the public as to the nature, quality or place of origin of the goods or services; and

6. where use of the trademark has been affirmed by the court's final decision to infringe another's copyright, patent or other rights.

This Article shall apply where a licensee/sublicensee has committed the act as referred to in Item 1 of the preceding paragraph, the trademark proprietor was well aware of or had prior knowledge of such act but failed to raise objection thereto.

Under the circumstances referred to in Item 2 of the first paragraph, where use of the registered trademark concerned has commenced at the time the cancellation proceedings are initiated, the registration shall not be cancelled, unless the trademark proprietor, being aware of other’s intent to initiate the cancellation proceedings, commenced using the trademark within three months prior to the date the cancellation proceedings are initiated.

Where the cause for cancellation is attributable to part of goods or services designated by the registered trademark, the cancellation may be limited to such goods or services.

A trademark proprietor shall be deemed to have used its registered trademark in either of the following cases:
1. where the trademark is used in a format not consistent with that as registered, however, the unity of the mark is maintained according to the general concept in society; and

2. where the registered trademark is indicated on the goods for export purposes or on the pertinent articles.

The Trademark Office shall notify the trademark proprietor of the cancellation proceedings and specify a time limit for filing a counter-statement. However, if the petitioner's request is not supported by concrete evidence or if its claim is obviously unjustifiable, the cancellation proceedings may be dismissed straightforwardly.
Under the circumstance referred to in Item 2, the first paragraph of Article 57, where a notification to submit counter-statement has been served, the trademark proprietor shall prove use of the trademark. The Trademark Office may proceed to cancel the registration in the absence of a counter-statement filed within the specified time limit.

The evidence submitted by the trademark proprietor to prove use as prescribed in the preceding paragraph shall comply with the general practice in the related trade.

After a trademark registration is cancelled pursuant to the provisions of Item 1 or 6, the first paragraph of Article 57, the trademark proprietor, within three years from the date of cancellation, shall not register or be recorded as an assignee or licensee/sublicensee of another trademark identical with or similar to the cancelled trademark in relation to the same or related goods or services. The provision shall apply as well where the trademark proprietor has declared to waive trademark rights before the Trademark Office renders a decision thereon.

The provisions of the second and third paragraphs of Article 40, the first and second paragraphs of Article 41, Articles 42 through 44 shall apply mutatis mutandis to trademark cancellation proceedings.