Exhibit 10.3

Amendment No. 1 to Service Agreement

Dated as of 17 September 2025

This Amendment No. 1 to Service Agreement (this “Amendment”) is made and entered into as of the date first set forth above (the “Amendment Date”), by and between HeartCore Enterprises, Inc., a Delaware corporation (the “PMO”) and KOEI JAPAN CO., LTD. (formerly Koei Shoji Co., Ltd.), a Japanese corporation (the “Company”). Each of the Company and PMO may be referred to herein individually as a “Party” and collectively as the “Parties.”

WHEREAS, the Parties are parties to that certain Service Agreement, dated as of 11 April 2024 (the “Original Agreement”); and

WHEREAS, the Parties now desire to amend the Original Agreement, and pursuant to the provisions of Section 11(f) of the Original Agreement the Parties may amend the Original Agreement in writing;

NOW, THEREFORE, in consideration of the mutual promises set forth herein, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties hereby agree as follows:

Section 1. Definitions. Capital terms used herein without definition shall have the meanings given in the Original Agreement.

Section 2. Amendment. Pursuant to the provisions of Section 11(f) of the Original Agreement, the Parties agree, and the Original Agreement is hereby amended, as follows:

Section 3. Remainder in Force. Other than as amended herein, the Original Agreement shall remain in full force and effect. Following the full execution of this Amendment, any references in the Original Agreement to the “Agreement” shall be deemed a reference to the Original Agreement as amended by this Amendment and the Original Agreement and this Amendment shall be interpreted and enforced as one combined agreement.

Section 4. Miscellaneous.

[Signatures appear on following page]

IN WITNESS WHEREOF, the Parties hereto have executed this Amendment as of the Amendment Date.

Exhibit A

First Series Stock Acquisition Rights Allotment Agreement

(Attached)

First Series Stock Acquisition Rights Allotment Agreement

HeartCore Enterprise, Inc. (hereinafter the “Holder”) and Koei Group Co., Ltd. (hereinafter the “Issuer”) enter into this First Series Stock Acquisition Rights Allotment Agreement (hereinafter the “Agreement”) on September 17, 2025 (hereinafter the “Effective Date”) with respect to the allotment of stock acquisition rights by the Issuer to the Holder, as set forth below.

This Agreement supersedes Appendix 3 (“Appendix 3”) of the service agreement (hereinafter the “Service Agreement”) entered into between the Holder and the Issuer on April 11, 2024, and is executed as a replacement thereof.

Furthermore, with respect to the rights referred to as the “Warrant” in Section 5.(a)(ii) of the Service Agreement, this Agreement specifies and defines such rights as stock acquisition rights under the Companies Act of Japan.

For the avoidance of doubt, in filings with or disclosures to U.S. securities regulators (including the U.S. Securities and Exchange Commission) and similar bodies, these stock acquisition rights may, for ease of communication to investors, be referred to as “Warrants”; however, their legal nature is that of stock acquisition rights under Japanese law.

If the Holder submits the Issuer’s prescribed written notice of waiver of all or part of the Stock Acquisition Rights, the waived portion can no longer be exercised.

Delivery of shares upon exercise (including issuance, transfer or assignment) shall not violate the matters prescribed in Article 238(1) of the Companies Act. The Holder shall comply with the Companies Act, Financial Instruments and Exchange Act, tax laws, and all other domestic and foreign laws in connection with exercise, disposition, and related transactions.

Each party represents and warrants that neither it nor its officers/employees is, or has been within five years, an organized crime group member or related entity, and covenants not to have or form such relationships or engage in violent or unlawful demands, threats, defamation, or similar acts. If breached, the other party may terminate this Agreement immediately without notice.

Each party shall indemnify the other for damages, losses, or expenses (including lost profits and reasonable attorney fees) arising from breach of its obligations hereunder, limited to damages ordinarily foreseeable.

The Issuer may terminate all or part of this Agreement if the Holder violates its terms and fails to cure after notice.

This Agreement becomes effective on the Effective Date and remains in force while the Stock Acquisition Rights exist. Provisions applicable to shares issued upon exercise survive their extinction, and Articles 6, 8, and 11–13 survive termination.

If any provision is held invalid or unenforceable, the remaining provisions remain fully effective, and the parties shall endeavor to amend the invalid portion to validly reflect their intent.

This Agreement is governed by and construed under Japanese law. Any disputes shall first be resolved through good-faith negotiation and, if unresolved, shall be subject to the exclusive jurisdiction of the Tokyo District Court as the court of first instance.

Any matters not provided herein shall be determined through good-faith consultation between the parties.

If the Issuer’s initial public offering (“IPO”) is not completed, the Issuer may declare this Agreement null and void and the Stock Acquisition Rights shall lapse automatically.

Notwithstanding such termination, the provisions of Articles 6 (Confidentiality), 7 (Exclusion of Anti-Social Forces), 8 (Indemnification), 11 (Term), 12 (Severability), and 13 (Governing Law and Jurisdiction) shall survive and remain in full force and effect.

Executed in duplicate on September 17, 2025.   Issuer: Koei Group Co., Ltd. Shinagawa Grand Central Tower, 2-16-3 Konan, Minato-ku, Tokyo Representative Director: Mamoru Iwamoto

Holder: HeartCore Enterprise, Inc. 848 Jordan Ave. Apt G, Los Altos, CA 94022 Director: Sumitaka Yamamoto

Attachment

Koei Group Co., Ltd. – Terms of Issuance of First Series Stock Acquisition Rights