Was Sun Kang’s Amprius Technologies (AMPX) share sale discretionary?

The sale was not discretionary. Footnotes state it was executed under non-discretionary, sell-to-cover arrangements mandated by Amprius Technologies to fund tax withholding obligations arising from the vesting of restricted stock units granted to Sun Kang.

Amprius Technologies (AMPX) director logs small tax sell-to-cover trade

Filing Impact

(Neutral)

Filing Sentiment

(Neutral)

Form Type

Rhea-AI Filing Summary

Amprius Technologies director Sun Kang reported a small tax-related share sale. On this Form 4, Kang disclosed an open-market sale of 356 shares of common stock on May 27, 2026 at an average price of $17.1935 per share.

According to the footnotes, this transaction was a non-discretionary sell-to-cover mandated by the company to fund tax withholding on vesting restricted stock units. After the sale, Kang held 1,280,498 shares directly, including 1,038,662 restricted stock units, and 56,406 shares indirectly through the Kang & Cecillia Sun Family Revocable Trust.

Insider Trade Summary

Net Seller: 356 shares ($6,121)

Net Sell 2 txns

Insider Sun Kang

Role null

Sold 356 shs ($6K)

Type	Security	Shares	Price	Value
Sale	Common stock	356	$17.1935	$6K
holding	Common stock	--	--	--

Holdings After Transaction: Common stock — 1,280,498 shares (Direct, null); Common stock — 56,406 shares (Indirect, See Footnote)

Footnotes (1)

This transaction was effected pursuant to non-discretionary, sell-to-cover arrangements mandated by the issuer to fund tax withholding obligations in connection with the vesting of restricted stock units. The price reported in Column 4 is an average execution price. These shares were sold in multiple transactions at prices ranging from $17.13 to $17.3, 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. Includes 1,038,662 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. These securities are held directly by the KANG & CECILLIA SUN FAMILY REVOCABLE TRUST, for which the reporting person and his spouse are co-trustees.

Key Figures

Shares sold: 356 shares Average sale price: $17.1935 per share Post-transaction direct holdings: 1,280,498 shares +3 more

6 metrics

Shares sold 356 shares Open-market sale on May 27, 2026 to cover tax withholding

Average sale price $17.1935 per share Mandated sell-to-cover transactions

Post-transaction direct holdings 1,280,498 shares Common stock directly held after sale, including RSUs

Restricted stock units 1,038,662 RSUs Each RSU represents a right to one common share, subject to vesting

Indirect trust holdings 56,406 shares Held by Kang & Cecillia Sun Family Revocable Trust

Sale price range $17.13–$17.30 per share Multiple trades within this range on May 27, 2026

Key Terms

sell-to-cover arrangements, restricted stock units, non-discretionary, average execution price, +1 more

5 terms

sell-to-cover arrangements financial

"non-discretionary, sell-to-cover arrangements mandated by the issuer to fund tax withholding obligations"

restricted stock units financial

"Includes 1,038,662 restricted stock units, each of which represents a contingent right"

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

non-discretionary financial

"This transaction was effected pursuant to non-discretionary, sell-to-cover arrangements mandated by the issuer"

average execution price financial

"The price reported in Column 4 is an average execution price"

revocable trust financial

"These securities are held directly by the KANG & CECILLIA SUN FAMILY REVOCABLE TRUST"

A revocable trust is a legal arrangement where the person who creates it keeps control and can change or cancel the trust at any time, while naming who will manage and receive the assets later. Think of it like a flexible folder for your investments and property that can be relabeled or reworked as circumstances change; it matters to investors because it determines how ownership is recorded, how easily assets transfer on incapacity or death, and whether holdings bypass public probate proceedings.

Form 4 Insider Transactions: What Each Field Means →

05/28/2026 - 06:24 PM

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^*

Sun Kang

(Last)

(First)

(Middle)

C/O AMPRIUS TECHNOLOGIES, INC.,

1180 PAGE AVENUE

(Street)

FREMONT

CALIFORNIA

94538

(City)

(State)

(Zip)

UNITED STATES

(Country)

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

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/27/2026

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common stock	05/27/2026		S⁽¹⁾		356	D	$17.1935⁽²⁾	1,280,498⁽³⁾	D
Common stock								56,406	I	See Footnote⁽⁴⁾

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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

Explanation of Responses:

1. This transaction was effected pursuant to non-discretionary, sell-to-cover arrangements mandated by the issuer to fund tax withholding obligations in connection with the vesting of restricted stock units.

2. The price reported in Column 4 is an average execution price. These shares were sold in multiple transactions at prices ranging from $17.13 to $17.3, 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.

3. Includes 1,038,662 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.

4. These securities are held directly by the KANG & CECILLIA SUN FAMILY REVOCABLE TRUST, for which the reporting person and his spouse are co-trustees.

Remarks:

	/s/ Ricardo C. Rodriguez, attorney-in-fact on behalf of Kang Sun	05/28/2026
	** 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)

Source: View Original Filing on SEC EDGAR

FAQ

What insider transaction did Sun Kang report for Amprius Technologies (AMPX)?

Sun Kang reported selling 356 shares of Amprius Technologies common stock. The sale occurred on May 27, 2026 at an average price of $17.1935 per share and was executed as a mandated, non-discretionary sell-to-cover for tax withholding on vested restricted stock units.

How many Amprius Technologies (AMPX) shares did Sun Kang hold after this Form 4?

After the reported transaction, Sun Kang held 1,280,498 Amprius Technologies shares directly and 56,406 shares indirectly. The direct holdings include 1,038,662 restricted stock units, each representing a contingent right to receive one share of common stock, subject to applicable vesting conditions.

What price range were Sun Kang’s Amprius Technologies (AMPX) shares sold at?

The reported average sale price was $17.1935 per share. Footnotes explain the 356 shares were sold in multiple trades at prices ranging from $17.13 to $17.30 per share, with full trade-level details available upon request from the reporting person.

How are Sun Kang’s indirect Amprius Technologies (AMPX) holdings structured?

Indirect holdings of 56,406 shares are held by the Kang & Cecillia Sun Family Revocable Trust. Sun Kang and his spouse serve as co-trustees of this trust, which is reported as the owner of those Amprius Technologies common shares on the Form 4 filing.

What role do restricted stock units play in Sun Kang’s Amprius Technologies (AMPX) position?

Restricted stock units form a large part of his reported holdings. The filing notes 1,038,662 restricted stock units, each representing a contingent right to receive one share of Amprius Technologies common stock, subject to vesting schedules and applicable conditions described in the award agreements.