Company: CNCKW
Filing Date: 2025-11-18
Form Type: 424B3
Source: 0001913847-25-000033
Chunk: 0

Company: Coincheck Group N.V.
Filing Date: 2025-11-18
Form: 424B3
Chunk 0
---
| PROSPECTUS SUPPLEMENT NO. 1                 
 (to the Prospectus dated September 5, 2025) |     | Filed Pursuant to Rule 424(b)(3) 
 Registration No. 333-284537      |

#### COINCHECK GROUP N.V.
<div align='center'>Primary Offering of</div>

#### 4,860,148 Ordinary Shares Underlying Warrants
<div align='center'>Secondary Offering of 127,559,143 Ordinary Shares
129,611 Warrants to Purchase Ordinary Shares and
129,611 Ordinary Shares Underlying Warrants</div>

This prospectus supplement amends the prospectus dated September 5, 2025 (as supplemented or amended from time to time, the “Prospectus”) of Coincheck Group N.V., which forms a part of our Registration Statement on Form F-1 (No. 333-284537). This prospectus supplement is being filed to update and supplement the information included in the Prospectus with our Unaudited Condensed Consolidated Interim Financial Statements as of September 30, 2025 and March 31, 2025 and for the three and six months ended September 30, 2025 and 2024 and the related Management’s Discussion and Analysis of Financial Condition and Results of Operations, included in our Report on Form 6-K, which was furnished to the Securities and Exchange Commission on November 14, 2025 (the “SEC”). Accordingly, we have attached Exhibit 99.1 to the aforementioned Report on Form 6-K. Capitalized terms used in this prospectus supplement and not otherwise defined herein have the meanings specified in the Prospectus.

Our Ordinary Shares and Public Warrants are listed on the Nasdaq Global Market (“Nasdaq”) under the symbols “CNCK” and “CNCKW,” respectively. Holders of Ordinary Shares and Public Warrants should obtain current market quotations for their securities. The last reported sale price for our Ordinary Shares on Nasdaq was $3.31 per share on November 14, 2025, and the last reported sale price for our Public Warrants on Nasdaq was $0.80 per warrant on November 13, 2025.

We are a “foreign private issuer” as defined under the U.S. federal securities laws and, as such, may elect to comply with certain reduced public company disclosure and reporting requirements. See “Prospectus Summary — Implications of Being a Foreign Private Issuer." See also,