[Form 4] SEALSQ Corp Insider Trading Activity

Rhea-AI Filing Summary

SEALSQ Corp director and CFO John Charles O'Hara sold 20,000 Ordinary Shares in two open-market transactions. On April 16, 2026, he sold 10,000 shares at a weighted average price of $2.6947 per share. On April 17, 2026, he sold another 10,000 shares at a weighted average price of $2.7210 per share. After these sales, he directly holds 326,095 Ordinary Shares. The filing states that the transactions were effected under a Rule 10b5-1 trading plan adopted on October 17, 2025, and that each reported price reflects a weighted average for multiple trades within disclosed price ranges.

Insider Trade Summary 10b5-1

Net Seller: 20,000 shares ($54,157)

Net Sell 2 txns

Insider O'Hara John Charles

Role Chief Financial Officer

Sold 20,000 shs ($54K)

Type	Security	Shares	Price	Value
Sale	Ordinary Shares	10,000	$2.721	$27K
Sale	Ordinary Shares	10,000	$2.6947	$27K

Holdings After Transaction: Ordinary Shares — 326,095 shares (Direct)

Footnotes (1)

1. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 17, 2025. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $2.60 to $2.7779, inclusive. The reporting person undertakes to provide to SEALSQ Corp, any security holder of SEALSQ Corp, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $2.6471 to $2.85, inclusive. The reporting person undertakes to provide to SEALSQ Corp, any security holder of SEALSQ Corp, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (3) to this Form 4.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

O'Hara John Charles

(Last) (First) (Middle)

C/O SEALSQ CORP

AVENUE LOUIS-CASAI 58

(Street)

COINTRIN 1216

(City) (State) (Zip)

SWITZERLAND

(Country)

2. Issuer Name and Ticker or Trading Symbol
SEALSQ Corp [ LAES ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Financial Officer

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
04/16/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Ordinary Shares	04/16/2026		S(1)		10,000	D	$2.6947(2)	336,095	D
Ordinary Shares	04/17/2026		S(1)		10,000	D	$2.721(3)	326,095	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 17, 2025.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $2.60 to $2.7779, inclusive. The reporting person undertakes to provide to SEALSQ Corp, any security holder of SEALSQ Corp, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $2.6471 to $2.85, inclusive. The reporting person undertakes to provide to SEALSQ Corp, any security holder of SEALSQ Corp, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (3) to this Form 4.

	/s/ John O'Hara	04/17/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)