[Form 4] Amprius Technologies, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Amprius Technologies, Inc. Chief Technology Officer Stefan Constantin Ionel reported option exercises and a related share sale. On January 28, 2026, he exercised stock options for 90 shares at $0.62 and 39,600 shares at $0.05, receiving the same number of common shares.

That same day, he sold 39,690 common shares at an average price of $12.0018, with individual trades ranging from $12.00 to $12.02. After these transactions, he directly beneficially owned 748,696 common shares, including 585,697 restricted stock units. All exercises and sales were made under a Rule 10b5-1 trading plan adopted on September 11, 2025.

Insider Trade Summary

Net Seller: 39,690 shares ($476,351)

Net Sell 5 txns

Insider Stefan Constantin Ionel

Role Chief Technology Officer

Sold 39,690 shs ($476K)

Type	Security	Shares	Price	Value
Exercise	Stock Option (right to buy)	90	$0.00	--
Exercise	Stock Option (right to buy)	39,600	$0.00	--
Exercise	Common stock	90	$0.62	$55.80
Exercise	Common stock	39,600	$0.05	$2K
Sale	Common stock	39,690	$12.0018	$476K

Holdings After Transaction: Stock Option (right to buy) — 0 shares (Direct); Common stock — 748,786 shares (Direct)

Footnotes (1)

1. The exercises and sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on September 11, 2025. Includes 585,697 restricted stock units, each of which represents a contingent right to receive one share of the issuer's common stock, subject to the applicable vesting schedule and conditions of each restricted stock unit. The price reported in Column 4 is an average execution price. These shares were sold in multiple transactions at prices ranging from $12.00 to $12.02, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 range set forth above.

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).

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^*

Stefan Constantin Ionel

(Last) (First) (Middle)

C/O AMPRIUS TECHNOLOGIES, INC.,

1180 PAGE AVENUE

(Street)

FREMONT CA 94538

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Amprius Technologies, Inc. [ AMPX ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
01/28/2026

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

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

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

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
Common stock	01/28/2026		M(1)		90	A	$0.62	748,786(2)	D
Common stock	01/28/2026		M(1)		39,600	A	$0.05	788,386(2)	D
Common stock	01/28/2026		S(1)		39,690	D	$12.0018(3)	748,696(2)	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
Stock Option (right to buy)	$0.62	01/28/2026		M(1)			90	10/23/2024	03/15/2027	Common stock	90	$0	0	D
Stock Option (right to buy)	$0.05	01/28/2026		M(1)			39,600	09/14/2022	03/15/2027	Common stock	39,600	$0	0	D

Explanation of Responses:

1. The exercises and sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on September 11, 2025.

2. Includes 585,697 restricted stock units, each of which represents a contingent right to receive one share of the issuer's common stock, subject to the applicable vesting schedule and conditions of each restricted stock unit.

3. The price reported in Column 4 is an average execution price. These shares were sold in multiple transactions at prices ranging from $12.00 to $12.02, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 range set forth above.

Remarks:

	/s/ Ricardo C. Rodriguez, attorney-in-fact on behalf of Constantin Ionel Stefan	01/30/2026
	** 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.

FAQ

What insider transaction did Amprius (AMPX) report for its CTO?

Amprius reported option exercises and a share sale by its CTO. On January 28, 2026, Stefan Constantin Ionel exercised options into 39,690 shares in total, then sold 39,690 common shares at an average price of about $12.00 per share under a Rule 10b5-1 plan.

How many Amprius (AMPX) shares did the CTO sell and at what price?

The CTO sold 39,690 Amprius common shares. These shares were sold on January 28, 2026, at an average price of $12.0018 per share, with individual trade prices ranging from $12.00 to $12.02, as disclosed in the Form 4 footnote.

What stock options did the Amprius (AMPX) CTO exercise in this Form 4?

The CTO exercised two stock option grants. He exercised options for 90 shares at an exercise price of $0.62 and 39,600 shares at an exercise price of $0.05, both converting into Amprius common stock on January 28, 2026, before the disclosed sale.

How many Amprius (AMPX) shares does the CTO own after these transactions?

After the transactions, the CTO beneficially owned 748,696 shares. This total includes 585,697 restricted stock units, each representing a contingent right to receive one share of Amprius common stock, subject to applicable vesting schedules and conditions described in the filing.

Was the Amprius (AMPX) CTO’s share sale pre-planned under a Rule 10b5-1 plan?

Yes, the exercises and sale were under a Rule 10b5-1 plan. The filing states that all reported option exercises and related stock sales were effected pursuant to a trading plan adopted by the reporting person on September 11, 2025.

What is notable about the pricing of the Amprius (AMPX) CTO’s share sale?

The sale used an average execution price disclosure. The reported average price was $12.0018 per share, with underlying trades executed between $12.00 and $12.02, and the insider offered to provide detailed price breakdowns upon request.