[SCHEDULE 13G/A] Cayson Acquisition Corp Unit SEC Filing

Rhea-AI Filing Summary

Mizuho Financial Group filed an amended Schedule 13G reporting beneficial ownership of 704,500 common shares of Cayson Acquisition Corp (CUSIP G1993W109), representing 9.0% of the class. The filing states Mizuho has sole voting and sole dispositive power over the reported shares, which signals control of voting and disposition for that block.

The filing identifies Mizuho as a Japan-organized parent holding company and notes that Mizuho Financial Group, Mizuho Bank, Ltd., and Mizuho Americas LLC may be deemed indirect beneficial owners through securities directly held by Mizuho Securities USA LLC. The statement certifies the shares were acquired and are held in the ordinary course of business and not to influence control. The filing is signed by Takahiro Katsura on 08/13/2025. Exhibit A is referenced for subsidiary identification.

Positive

• Material institutional stake: Reporting ownership of 704,500 shares (9.0%) is above the 5% reporting threshold.
• Sole voting and dispositive power: Mizuho reports sole authority to vote and dispose of the reported shares, clarifying control of that block.
• Certification of ordinary-course holding: Filing states the shares are held in the ordinary course of business and not to influence control.

Negative

• Exhibit A referenced but not provided in the supplied content, limiting clarity on the specific subsidiary that acquired the securities.
• No acquisition details disclosed (e.g., purchase date or price) beyond the event date field, reducing transparency about timing and cost basis.

Insights

Securities Analyst

TL;DR: Mizuho reports a material 9.0% stake (704,500 shares) in Cayson Acquisition with sole voting and dispositive power, filed as a Schedule 13G/A.

The holding exceeds the 5% disclosure threshold and therefore is material to shareholders and market observers. The filing explicitly states sole voting and dispositive power, which means Mizuho can direct votes and dispositions for the 704,500 shares reported. However, the required certification declares the position is held in the ordinary course of business and not for the purpose of changing control, which frames this as a passive institutional stake rather than an activist position. The document references Exhibit A for subsidiary identification but does not include that exhibit in the provided content.

Corporate Governance Expert

TL;DR: A 9.0% beneficial holding with sole voting power is governance-relevant but the filer certifies no intent to influence control.

From a governance perspective, sole voting authority over a >5% block gives the reporting person the legal ability to influence shareholder votes should they choose. The filing’s explicit certification that the shares are held in the ordinary course of business reduces the immediate implication of an intent to change control. The disclosure also clarifies the parent/subsidiary ownership chain by naming related entities and the broker/holding subsidiary involved, though the referenced Exhibit A identifying the acquiring subsidiary is not present in the provided content.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 3)

Cayson Acquisition Corp

(Name of Issuer)

Common Shares

(Title of Class of Securities)

G1993W109

(CUSIP Number)

06/30/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. G1993W109

1

Names of Reporting Persons

Mizuho Financial Group, Inc.

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

JAPAN

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 704,500.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 704,500.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

704,500.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

9.0 %

12

Type of Reporting Person (See Instructions)

FI

Comment for Type of Reporting Person: Mizuho Financial Group, Inc., Mizuho Bank, Ltd. and Mizuho Americas LLC may be deemed to be indirect beneficial owners of said equity securities directly held by Mizuho Securities USA LLC which is their wholly-owned subsidiary.

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Cayson Acquisition Corp
(b)	Address of issuer's principal executive offices: 205 W 37TH ST NEW YORK, NY, 10018
Item 2.
(a)	Name of person filing: Mizuho Financial Group, Inc.
(b)	Address or principal business office or, if none, residence: 1-5-5, Otemachi, Chiyoda-ku, Tokyo, 100-8176, Japan
(c)	Citizenship: Japan
(d)	Title of class of securities: Common Shares
(e)	CUSIP No.: G1993W109
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
	Parent Holding Company
Item 4.	Ownership
(a)	Amount beneficially owned: 704,500
(b)	Percent of class: 9.0 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 704,500
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 704,500
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	Ownership of 5 Percent or Less of a Class.
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary. See Exhibit A
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11. By signing below I certify that, to the best of my knowledge and belief, the foreign regulatory scheme applicable to Parent Holding Company is substantially comparable to the regulatory scheme applicable to the functionally equivalent U.S. institution(s). I also undertake to furnish to the Commission staff, upon request, information that would otherwise be disclosed in a Schedule 13D.

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.

Mizuho Financial Group, Inc.

Signature:	/s/ Takahiro Katsura
Name/Title:	Takahiro Katsura, Managing Director, Global Corporate Function Coordination Department
Date:	08/13/2025

FAQ

How many Cayson Acquisition (CAPNU) shares does Mizuho report owning?

Mizuho reports beneficial ownership of 704,500 shares of Cayson Acquisition common stock.

What percentage of CAPNU does Mizuho own according to the filing?

The filing states Mizuho owns 9.0% of the class.

Does Mizuho have voting authority over its CAPNU shares?

Yes. The filing reports sole voting power and sole dispositive power for the 704,500 shares.

Is Mizuho intending to influence control of Cayson Acquisition per the filing?

The filing includes a certification that the shares were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control.

Who signed the Schedule 13G/A for Mizuho and when?

The filing is signed by Takahiro Katsura, Managing Director, Global Corporate Function Coordination Department, dated 08/13/2025.

Does the filing identify related Mizuho entities as indirect owners of the CAPNU shares?

Yes. It states that Mizuho Financial Group, Mizuho Bank, Ltd. and Mizuho Americas LLC may be deemed indirect beneficial owners through securities directly held by Mizuho Securities USA LLC.