Kang Sun - 01 Apr 2026 Form 4 Insider Report for Amprius Technologies, Inc. (AMPX)

Reporting relationship: Director
Issuer ticker: AMPX
Reported as of: 01 Apr 2026
Net transaction value: -$23,860,714
SEC form: 4
Accepted by SEC: 02 Apr 2026, 16:51:04 UTC
Prior SEC filing: 24 Mar 2026
Next SEC filing: 07 May 2026
Source filing: View source filing
Reporting owner signature: /s/ Ricardo C. Rodriguez, attorney-in-fact on behalf of Kang Sun

Key filing fact

Kang Sun filed Form 4 for Amprius Technologies, Inc. (AMPX) on 02 Apr 2026.

Key facts

This page summarizes Kang Sun's Form 4 filing for Amprius Technologies, Inc. (AMPX).
6 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 02 Apr 2026, 16:51.

Change

Previous filing in this sequence was filed on 24 Mar 2026.
Current net transaction value: -$23,860,714.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001476220 Primary reporting owner

Sun Kang

Relationship: Director
Address: C/O AMPRIUS TECHNOLOGIES, INC.,, 1180 PAGE AVENUE, FREMONT
Signature: /s/ Ricardo C. Rodriguez, attorney-in-fact on behalf of Kang Sun
Signature date: 02 Apr 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

AMPX transaction

Common stock

Options Exercise

Transaction value
Shares: +1,312,505
Change %: +98%
Price: $1.78^*
Shares after: 2,654,905
Date: 01 Apr 2026
Ownership: Direct
Footnotes: F1, F2

AMPX transaction

Common stock

Options Exercise

Transaction value
Shares: +187,495
Change %: +7.1%
Price: $3.68^*
Shares after: 2,842,400
Date: 01 Apr 2026
Ownership: Direct
Footnotes: F1, F2

AMPX transaction

Common stock

Sale

Transaction value: $19,681,151
Shares: -1,250,963
Change %: -44%
Price: $15.73
Shares after: 1,591,437
Date: 01 Apr 2026
Ownership: Direct
Footnotes: F1, F2, F3

AMPX transaction

Common stock

Sale

Transaction value: $4,179,563
Shares: -249,037
Change %: -16%
Price: $16.78
Shares after: 1,342,400
Date: 01 Apr 2026
Ownership: Direct
Footnotes: F1, F2, F4

AMPX holding

Common stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 56,406
Date: 01 Apr 2026
Ownership: See Footnote
Footnotes: F5

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

AMPX transaction Derivative

Stock Option (right to buy)

Options Exercise

Transaction value
Shares: -1,312,505
Change %: -100%
Price: $1.78^*
Shares after: 0
Date: 01 Apr 2026
Ownership: Direct
Underlying class: Common stock
Underlying amount: 1,312,505
Exercise price: $1.78
Footnotes: F1

AMPX transaction Derivative

Stock Option (right to buy)

Options Exercise

Transaction value
Shares: -187,495
Change %: -9.5%
Price: $3.68^*
Shares after: 1,787,007
Date: 01 Apr 2026
Ownership: Direct
Underlying class: Common stock
Underlying amount: 187,495
Exercise price: $3.68
Footnotes: F1

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 5 footnotes

Footnote F1

The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 18, 2025.

Footnote F2

Includes 1,159,385 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.

Footnote F3

The price reported in Column 4 is an average execution price. These shares were sold in multiple transactions at prices ranging from $15.37 to $16.36, 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.

Footnote F4

The price reported in Column 4 is an average execution price. These shares were sold in multiple transactions at prices ranging from $16.37 to $17.31, 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.

Footnote F5

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