YMAT 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 December 2025.

Commission File Number 001-42767

J-Star Holding Co., Ltd.

(Translation of registrant’s name into English)

7/F-1, No. 633, Sec. 2, Taiwan Blvd.,

Xitun District, Taichung City 407,

Taiwan (R.O.C.)

(Address of principal executive office)

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

Form 20-F ☒ Form 40-F

INFORMATION CONTAINED IN THIS FORM 6-K REPORT

As a company incorporated in the Cayman Islands that is listed on Nasdaq Capital Market (“Nasdaq”), the Company is subject to the Nasdaq corporate governance listing standards. Under Nasdaq rules, a foreign private issuer may, in general, follow its home country corporate governance practices in lieu of some of the Nasdaq corporate governance requirements. Pursuant to the home country rule exemption set forth under Nasdaq Listing Rule 5615(a)(3), a Foreign Private Issuer may follow its home country practice in lieu of the requirements of the Nasdaq Marketplace Rule 5600 Series, including Rule 5640.

Ogier, the counsel to the Company as to the laws of Cayman Islands, has provided a letter of confirmation, as required by the Nasdaq Stock Market, confirming that the governance practices adopted by the Company, in lieu of those Nasdaq corporate governance requirements where it is electing to follow local country laws and regulations (as referenced above), are compliant with the provisions of the laws of the Cayman Islands and its fourth amended and restated memorandum and articles of association in connection with the Company’s adoption of the dual class share capital structure..

A copy of the home country rule exemption letter from the Company’s legal counsel is attached hereto as Exhibit 99.1.

Submission of Matters to a Vote of Security Holders.

On December 9, 2025, J-Star Holding Co., Ltd (the “Company”) held the Company’s General Meeting (the “GM”) at 10:30 a.m. (Taiwan time and date) /F-1, No. 633, Sec. 2, Taiwan Blvd., Xitun District, Taichung City 407, Taiwan (R.O.C.). On November 3, 2025 (the “Record Date”), the record date for the GM, there were 17,200,387 of the Company’s ordinary shares outstanding and entitled to vote at the GM. 11,513,328 Ordinary Shares, which represented approximately 66.94% of the votes of the outstanding ordinary shares in the Company as of the Record Date, were represented in person or by proxy. Five items of business were acted upon by the Company’s shareholders at the GM, each of which was approved by the Company’s shareholders.

such that the authorized share capital of the Company shall become US$17,500,000 divided into (a) 28,902,817 class A ordinary shares of a par value of US$0.50 each and (b) 6,097,183 class B ordinary shares of a par value of US$0.50 each (the “Share Capital Reorganisation”).”

The voting results were as follows:

Exhibits

SIGNATURES

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.

Exhibit 99.1

5 December 2025

Dear Sirs and/or Madams

We act as the Cayman Islands counsel to J-Star Holding Co., Ltd. 家星控股股份有限公司, an exempted company incorporated in the Cayman Islands (the “Company”).

Pursuant to Listing Rule 5615(a)(3), please be informed hereby that the Company has elected to follow its Cayman Islands practice in lieu of the following Nasdaq Stock Market LLC Rules (the “Rules”). Rule 5640 requiring the voting rights of existing shareholders of publicly traded shares of a Nasdaq-listing company registered under section 12 of The Securities Exchange Act of 1934 of the United States cannot be disparately reduced or restricted through any corporate action or issuance, which includes without limitation, the adoption of time-phased voting plans, the adoption of capped voting rights plans, the issuance of super-voting stock, or the issuance of stock with voting rights less than the per share voting rights of the existing common stock through an exchange offer.

Under Cayman Islands law, it is permissible for the Company to adopt a dual class share capital structure comprised of class A ordinary shares of US$0.50 par value each (the Class A Ordinary Shares) and class B ordinary shares of US$0.50 par value each (the Class B Ordinary Shares), where each Class A Ordinary Share has one vote each and each Class B Ordinary Share has ten (10) votes each, such rights to be stipulated in the Company’s fifth amended and restated memorandum and articles of association of the Company to be adopted by special resolution of the Company (the Draft Fifth Restated MAA).

The adoption of dual class share capital structure by the Company is not prohibited by the Companies Act (Revised) of the Cayman Islands, provided that such dual class share capital structure, including the adoption of the Draft Fifth Restated MAA, has been duly authorised and adopted by the Company in accordance its memorandum and articles of association then in effect.

We have made no investigation of and express no opinion in relation to the laws, rules or regulations of any jurisdiction other than those of the Cayman Islands. Specifically, we have made no independent investigation of the laws of the State of New York or the NASDAQ Stock Market LLC Rules, and we express no opinion as to the meaning, validity or effect of the NASDAQ Stock Market LLC Rules. This advice is to be governed by and construed in accordance with the laws of the Cayman Islands and is limited to and is given on the basis of the current law and practice in the Cayman Islands. This advice is issued solely for your benefit and is not to be relied upon by any other person, firm or entity or in respect of any other matter.

As required by Listing Rule 5615(a)(3), the Company will disclose in its Form 20-F each requirement of Listing Rule 5600 that it does not follow and describe the home country practice followed in lieu of such requirements.

Yours faithfully

Ogier