SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 1)

Coincheck Group N.V.

(Name of Issuer)

Ordinary Shares

(Title of Class of Securities)

N20967118

(CUSIP Number)

Yuko Seimei
Monex Group, Inc., ARK Mori Building 25F 1-12-32
Akasaka, Minato-ku, Tokyo, M0, 107-6025
81-3-4323-8698

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

05/12/2026

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. Checkbox not checked

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

CUSIP Number(s):

N20967118

Name of reporting person

MONEX GROUP, INC.

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

SEC use only

Source of funds (See Instructions)

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox not checked

Citizenship or place of organization

JAPAN

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 136,247,594.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 136,247,594.00
10	Shared Dispositive Power 0.00

Aggregate amount beneficially owned by each reporting person

136,247,594.00

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in Row (11)

83.6 %

Type of Reporting Person (See Instructions)

SCHEDULE 13D

Item 1.

Security and Issuer

(a)

Title of Class of Securities:

Ordinary Shares

(b)

Name of Issuer:

Coincheck Group N.V.

(c)

Address of Issuer's Principal Executive Offices:

Nieuwezijds Voorburgwal 162, Amsterdam, NETHERLANDS , 1012 SJ.

Item 1 Comment:

This Amendment No. 1 ("Amendment No. 1") to Schedule 13D relates to the ordinary shares ("Ordinary Shares") of Coincheck Group N.V. (the "Issuer"), and amends and supplements the initial statement on Schedule 13D filed on March 19, 2026 (as so amended, the "Schedule 13D"). Capitalized terms used but not defined in this Amendment No. 1 shall have the same meanings ascribed to them in the Schedule 13D.

Item 4.

Purpose of Transaction

Item 4 of the Schedule 13D is hereby amended and supplemented by the following: The information in Item 6 of this Schedule 13D is incorporated herein by reference.

Item 6.

Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer

Item 6 of the Schedule 13D is hereby amended and supplemented by the following: On May 12, 2026, the Issuer and KDDI Corporation ("KDDI") entered into a Share Subscription and Investor Rights Agreement ("SSA"), pursuant to which, among other things, KDDI has the right pursuant to the SSA to designate one non-executive director nominee (the "KDDI Nominee") to serve on the board of directors of the Issuer (the "Board"). Concurrently with entering into the SSA, the Reporting Person agreed to enter into an Acknowledgement Agreement with KDDI (the "Acknowledgement Agreement"), the execution and delivery of which is a condition precedent to the completion and closing of the SSA. Pursuant to the terms of the Acknowledgement Agreement, the Reporting Person has agreed to vote all Ordinary Shares (and any other voting securities) of the Issuer held by it to elect, at each general meeting of the Issuer where the KDDI Nominee is to be voted upon, the KDDI Nominee, as proposed by the Board in accordance with the SSA and the governance documents of the Issuer, as a member of the Board, unless the appointment of such nominee would constitute a violation of any applicable laws. The Acknowledgement Agreement shall be terminated if the parties agree in writing to terminate such agreement, KDDI ceases to have the right to nominate a KDDI Nominee under the SSA, or the SSA is terminated. The foregoing description of the Acknowledgement Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of such agreement, a copy of which is filed as Exhibit 99.4 to this Schedule 13D and is incorporated herein by reference.

Item 7.

Material to be Filed as Exhibits.

99.4 Acknowledgement Agreement, dated as of May 12, 2026, by and between Monex Group, Inc. and KDDI Corporation

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

MONEX GROUP, INC.

Signature:	/s/ Yuko Seimei
Name/Title:	Yuko Seimei, Representative Executive Officer
Date:	05/14/2026

Amendment: SEC Form SCHEDULE 13D/A filed by Coincheck Group N.V.