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Amprius Technologies director Sun Kang sold 61,251 shares of common stock on February 23, 2026 at an average price of $10.1555. According to the filing, this was a non-discretionary, sell-to-cover transaction mandated by the company to fund tax withholding on vesting restricted stock units.
After this sale, Kang directly holds 1,342,400 shares of Amprius common stock, which includes 1,159,385 restricted stock units. He also has indirect ownership of 274,275 shares through the KANG & CECILLIA SUN FAMILY REVOCABLE TRUST, where he and his spouse serve as co-trustees.
Amprius Technologies Chief Technology Officer Stefan Constantin Ionel reported an open-market sale of 25,366 shares of common stock at an average price of $10.1555 per share. The sale was made under a non-discretionary, issuer-mandated sell-to-cover arrangement for tax withholding on vesting restricted stock units. After the transaction, he holds 723,330 shares, including 533,440 restricted stock units that may convert into common stock as they vest.
AMPX submitted a Form 144 notice disclosing proposed and completed transactions in its common stock. The filing records a release of restricted stock units of 126,191 shares on 02/20/2026. The excerpt also lists 10b5-1 sales attributed to KANG SUN: 506,267 shares on 01/12/2026 for $5,111,474.14, 950,548 shares on 01/16/2026 for $10,518,669.11, and 43,185 shares on 01/20/2026 for $476,274.41.
AMPX insider transactions: Stefan Constantin Ionel reported multiple 10b5-1 sales of AMPX common stock on 12/11/2025, 01/21/2026, 01/22/2026, 01/23/2026, 01/28/2026, and 01/22/2026 (see amounts below). The filing also records a release of restricted stock units of 52,257 shares on 02/20/2026 labeled as Compensation.
Representative 10b5-1 sales shown include 125,000 shares on 12/11/2025 (proceeds 1313575) and 492,827 shares on 01/22/2026 (proceeds 5931912.19). Broker listed: Morgan Stanley Smith Barney LLC.
Amprius Technologies has terminated its lease for approximately 774,155 rentable square feet at a Colorado property in Brighton. The lease termination agreement with Starboard Platform Brighton JV, LLC became effective on January 31, 2026, releasing both parties from most future obligations under the lease.
To end the 15-year lease, which began in June 2024, Amprius paid a $20,000,000 termination fee. The landlord will return the company’s security deposit, currently held as a $1,200,000 letter of credit, on or before February 5, 2026. The company’s base rent for the Colorado property was approximately $300,000, plus about $190,000 in additional rent for operating expenses, insurance, and real estate taxes, with base rent subject to annual increases of about 3.3%.
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.
Amprius Technologies Chief Technology Officer Stefan Constantin Ionel reported a series of stock option exercises and share sales in January 2026. Between January 21 and 23, 2026, he exercised multiple stock options with exercise prices ranging from $0.05 to $0.62 per share, converting them into common stock.
On those same dates he sold several blocks of common stock, including 73,280 shares at an average price of $12.0007, 492,827 shares at an average price of $12.0365, and 1,600 shares at $12.00, all under a Rule 10b5-1 trading plan adopted on September 11, 2025. Following these transactions, he directly owned 748,696 shares of common stock, which includes 585,697 restricted stock units that may settle into shares if their vesting conditions are met.
Amprius Technologies insider plans sizable stock sale. A Form 144 filing indicates that Stefan Constantin Ionel intends to sell 717,307 shares of AMPX common stock through Morgan Stanley Smith Barney LLC on the NYSE, with an approximate market value of $8,012,319.19. The filing notes that 130,483,838 shares of the company’s common stock are outstanding.
The shares to be sold were acquired on 01/21/2026 through the cash exercise of stock options for the same 717,307-share amount. The form also reports prior sales over the past three months, including 125,000 and 73,255 shares sold on 12/11/2025 for gross proceeds of $1,313,575.00 and $769,807.49, and 25,024 shares sold on 11/21/2025 for $252,274.45. The filing includes a representation that the seller is not aware of undisclosed material adverse information about the issuer’s operations.
Amprius Technologies director Kang Sun reported option exercises and share sales under a pre-arranged trading plan. On January 16, 2026, he exercised stock options for 850,338 shares at $2.5 per share and 100,210 shares at $1.78 per share, then sold 950,548 shares of common stock at an average price of $11.0659 per share. On January 20, 2026, he exercised options for 43,185 shares at $1.78 per share and sold the same number of shares at an average price of $11.0287 per share.
Following these transactions, Sun directly beneficially owned 1,403,651 shares of Amprius common stock, including 1,285,576 restricted stock units, and indirectly held 274,275 shares through the Kang & Cecillia Sun Family Revocable Trust, where he and his spouse are co-trustees. The filing states that the exercises and sales were effected pursuant to a Rule 10b5-1 trading plan adopted on August 18, 2025.
A shareholder filed a Form 144 to sell 1,018,875 common shares on the NYSE, showing an aggregate market value of $10,341,581.25. The shares are to be sold through Morgan Stanley Smith Barney LLC, with an approximate sale date of 01/16/2026, and the filing notes that 130,483,838 shares of the issuer’s stock are outstanding.
The securities to be sold were acquired on 01/16/2026 via the exercise of stock options from the issuer, paid in cash. Over the past three months, the same account reported additional common stock sales, including 1,000,000 shares sold on 11/17/2025 for $10,595,300.00 and 506,267 shares sold on 01/12/2026 for $5,111,474.14, some under a Rule 10b5-1 trading plan.