6-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of June 2025

Commission File Number: 001-41965

Semilux International Ltd.

(Registrant’s Name)

4F., No. 32, Keya Rd., Daya Dist.

Central Taiwan Science Park

Taichung City 42881

Taiwan

(Address of Principal Executive Offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F ☒         Form 40-F ☐

Appointment of Directors or Certain Officers.

On June 2, 2025, the Board of Directors of Semilux International Ltd. (the “Company”) appointed Ms. Shu-Chuan Chien as a member of the Board of Directors, effective immediately. Ms. Chien fills the vacancy created by the resignation of Mr. Kwan Sun, which was previously disclosed by the Company in its Form 6-K filed on May 15, 2025.

In addition to her appointment to the Board, Ms. Chien has also been appointed to serve as a member of the Company’s Audit Committee.

Ms. Chien serves as the General Manager of Xuyao International Industrial Co., Ltd., where she is responsible for the company’s overall strategic direction, operations, and business development, including oversight of financial performance and internal controls. Prior to joining Xuyao, Ms. Chien served as Procurement Section Manager at Hua Hao Electronics Co., Ltd., where she led strategic sourcing initiatives and managed supplier relationships across global markets. Ms. Chien has over 20 years of experience in corporate management, procurement, and international business operations, with a focus on supply chain optimization, cost control, risk assessment, and cross-border business development. She holds a degree in International Trade from Aletheia University in Taiwan.

The Company also entered into an indemnity agreement with Ms. Chien in the same form as its standard form of indemnification agreement with its other directors.

The Company confirms that there are no related party transactions between Ms. Chien and the Company that would require disclosure under Item 7.B of Form 20-F. Any compensation arrangements in connection with her appointment will be disclosed, if applicable, in a subsequent filing.

Press Release Announcing Receipt of the NasdaqDelinquency Notice

On May 27, 2025, the Company received a delinquency notice (the “Notice”) from the Listing Qualifications Department of The Nasdaq Stock Market LLC (“Nasdaq”), indicating that the Company is not in compliance with Nasdaq Listing Rule 5250(c)(1) due to its failure to timely file its Annual Report on Form 20-F for the fiscal year ended December 31, 2024, with the U.S. Securities and Exchange Commission.

On June 2, 2025, the Company issued a press release regarding the receipt of the Notice. A copy of the press release is furnished as Exhibit 99.1 to this Form 6-K.

Exhibit Index

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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Exhibit 99.1

Semilux Receives Notification of Deficiency from Nasdaq Related to Delayed Filing of Annual Report on Form 20-F

Taipei, Taiwan, June 02, 2025 (GLOBE NEWSWIRE) -- Semilux International Ltd. (NASDAQ:SELX) (“SELX” or the “Company”) announced that it received a delinquency notification letter on May 27, 2025 (the “Deficiency Letter”) from the Listing Qualifications Department of The Nasdaq Stock Market Inc. (the “Nasdaq”) notifying the Company that it is no longer in compliance with the Nasdaq Listing Rule 5250(c)(1) (the “Listing Rule”) for continued listing due to its failure to timely file its annual report on Form 20-F for the year ended December 31, 2024 (the “Annual Report”) with the U.S. Securities and Exchange Commission. The Listing Rule requires Nasdaq-listed companies to timely file all required periodic reports with the SEC.

In accordance with Nasdaq’s listing rules, the Company has 60 calendar days after the Deficiency Letter to submit a plan to regain compliance with the Listing Rule. Following receipt of such plan, Nasdaq may, at its discretion, grant an extension of up to 180 calendar days from the Annual Report’s due date, or until November 11, 2025, for the Company to regain compliance.

The Company was not able to file the Annual Report by the prescribed deadline as extended pursuant to Rule 12b-25(b)(2)(ii) under the Securities Exchange Act of 1934 primarily due to additional time being required to finalize its financial statements and complete the preparation of the Annual Report for the fiscal year ended December 31, 2024. The Company continues to work diligently to complete the Annual Report and intends to file it with the SEC as soon as reasonably practicable.

The Deficiency Letter has no immediate impact on the listing of the Company's ordinary shares on the Nasdaq Capital Market. This announcement is made in compliance with the Nasdaq Listing Rule 5810(b), which requires prompt disclosure of receipt of a notification of deficiency.

About Semilux International Ltd.

Semilux is domiciled in the Cayman Islands and operates through its subsidiaries, Taiwan Color Optics, Inc. (“TCO”) and Semilux Ltd. TCO is an optical and 3D sensing technology company that is primarily involved in the customization, design and supply of optical components and integrated chip for various industries including autonomous driving, intelligent lighting, as well as unmanned aerial vehicles. In collaboration with its clients, TCO conceptualizes and produces high precision optics and sensing modules that are specifically customized to clients’ needs for ease of integration in overall design and production. Applications for TCO’s products include automotive laser headlight systems, adaptive driving beams (ADB) as well as light detection and autonomous driving systems (LiDAR). More information can be found at: http://www.semilux.com.

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Safe Harbor Statement

This press release may contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, including those regarding SELX's expectations, intentions, strategies, and beliefs pertaining to future events or future financial performance. Actual events or results may differ materially from those in the forward-looking statements because of various important factors, including those described in the Company's most recent filings with the SEC. SELX assumes no obligation to update publicly any such forward-looking statements, whether because of new information, future events or otherwise. For a more complete description of the risks that could cause our actual results to differ from our current expectations, please see the sections entitled but not limited to, “Management's Discussion and Analysis of Financial Condition and Results of Operations” and “Risk Factors” in SELX's annual reports on Form 20-F and interim reports on Form 6-K filed with the SEC, as such factors may be updated from time to time in SELX's periodic filings with the SEC, which are accessible on the SEC's website at www.sec.gov and at www.semilux.com.

Investor Relations Contact:

Email: [email protected]

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