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Amprius Technologies director Sun Kang reported multiple option exercises and a share sale. On January 12, 2026, he exercised three stock option grants for 180,802 shares at $0.62, 208,264 shares at $2.44, and 117,201 shares at $2.50 per share, receiving the same number of common shares in each case. He then sold 506,267 shares of common stock at an average price of $10.0964 under a Rule 10b5-1 trading plan adopted on August 18, 2025.
After these transactions, Sun directly beneficially owned 1,403,651 shares of common stock, which includes 1,285,576 restricted stock units, and held 850,338 stock options directly. In addition, 274,275 shares are held indirectly by the KANG & CECILLIA SUN FAMILY REVOCABLE TRUST, for which he and his spouse serve as co-trustees.
A holder of AMPX common stock has filed a notice of proposed sale under Rule 144 after exercising stock options. The filer plans to sell 506,267 common shares through Morgan Stanley Smith Barney LLC on the NYSE, with an indicated aggregate market value of 4,799,411.16. The approximate sale date is 01/12/2026, and the shares were acquired the same day by cash exercise of stock options from the issuer.
The notice also reports prior sales of the issuer’s common stock during the past three months by the same seller. These include 68,655 shares sold on 11/21/2025 for gross proceeds of 692,131.65, and 1,000,000 shares sold on 11/17/2025 under a Rule 10b5-1 trading plan for gross proceeds of 10,595,300.00. The filing represents that the seller is not aware of undisclosed material adverse information about the issuer.
Amprius Technologies, Inc. reported that it has completed all sales under its at-the-market equity offering program. The program, established under a sales agreement with B. Riley Securities, Cantor Fitzgerald and H.C. Wainwright, authorized offers of common stock up to an aggregate offering price of $100.0 million.
The company issued a total of 25.5 million shares of common stock through this program, generating aggregate net proceeds of approximately $97.5 million. During the three months ended December 31, 2025, Amprius sold additional shares for aggregate net proceeds of about $19.6 million at an average price of $11.17 per share, at which point the program was concluded and the sales agreement terminated in accordance with its terms.
Amprius Technologies, Inc. disclosed that a director and officer serving as President received an equity award in the form of restricted stock units. On December 19, 2025, the reporting person acquired 200,000 shares of common stock at a price of $0, as noted in a footnote describing these shares as restricted stock units granted on that date, with a vesting commencement date of January 1, 2026.
Each restricted stock unit represents the right to receive one share of Amprius common stock. One quarter of the award will vest on February 20, 2027, and the remaining units will vest in equal quarterly installments over the following three years on May 20, August 20, November 20 and February 20, until fully vested on February 20, 2030, subject to continued service. After this transaction, the reporting person beneficially owns 610,000 shares, including 600,000 restricted stock units subject to their respective vesting schedules and conditions.
Amprius Technologies announced a leadership transition. Chief Executive Officer Dr. Kang Sun told the board he will step down from his officer role effective December 31, 2025, and become Executive Advisor on January 1, 2026, while remaining on the board. The company states his decision is not due to any disagreement over operations, policies, or practices.
Amprius entered into a new employment agreement with Dr. Sun, giving him a $633,000 annual salary without bonus eligibility and providing six months of salary continuation and partial accelerated equity vesting if he is terminated without cause, resigns for good reason, or upon death or disability, with full stock option vesting if this occurs in connection with a change in control. Current President Tom Stepien has been appointed Chief Executive Officer effective January 1, 2026, with a $633,000 base salary, a target annual cash bonus equal to 100% of salary, and a grant of 200,000 restricted stock units that vest over four years.
Amprius Technologies’ Chief Technology Officer reported option exercises and share sales in December. On 12/11/2025, he exercised stock options for 125,000 shares of common stock at an exercise price of $0.05 per share, increasing his direct holdings.
On the same date, he sold 198,255 shares of common stock at an average price of $10.5086 per share, with individual trade prices ranging from $10.14 to $11.49. After these transactions, he directly held 748,696 shares, which includes 585,697 restricted stock units that vest over time, and 310,962 stock options remained outstanding. The exercises and sales were carried out under a Rule 10b5-1 trading plan adopted on September 11, 2025.
A shareholder has filed to sell common stock under Rule 144. The notice covers a proposed sale of 198,255 common shares through Morgan Stanley Smith Barney LLC on the NYSE, with an aggregate market value of $2,188,735.20 and 130,483,838 shares of the class outstanding.
The shares to be sold come from recent and prior equity awards, including 125,000 shares acquired on December 11, 2025 through a stock option exercise for cash, 43,464 shares from restricted stock units granted on May 20, 2024, and 29,791 shares from stock options previously exercised on December 14, 2022. In the past three months, the seller, Stefan Constantin Ionel, already sold 25,024 common shares on November 21, 2025 for gross proceeds of $252,274.45.
Amprius Technologies, Inc. insider transaction: the company’s Chief Technology Officer, Constantin Ionel Stefan, reported the sale of 25,024 shares of Amprius common stock on 11/21/2025 at an average price of $10.0813 per share, according to a Form 4 filing. The transaction is coded as a sale and was carried out under a non-discretionary sell-to-cover arrangement mandated by the company to fund tax withholding obligations tied to the vesting of restricted stock units, meaning the sale was made to cover taxes rather than as an open-market discretionary sale. After this transaction, Stefan beneficially owns 821,951 shares of Amprius common stock, which includes 585,697 restricted stock units that each represent a right to receive one share of common stock if their vesting conditions are met.
Amprius Technologies (AMPX) CEO Kang Sun reported an automatic sale of company stock. On 11/21/2025, he disposed of 68,655 shares of Amprius common stock at an average price of $10.0813 per share in a transaction coded "S." The sale was carried out under a non-discretionary, sell-to-cover arrangement mandated by the company to fund tax withholding obligations tied to the vesting of restricted stock units, meaning the sale was for tax purposes rather than an open-market portfolio decision.
Following this transaction, Kang Sun beneficially owned 1,403,651 shares directly, which include 1,285,576 restricted stock units that may convert into common shares if vesting conditions are met. He also indirectly held 274,275 shares through the KANG & CECILLIA SUN FAMILY REVOCABLE TRUST, where he and his spouse serve as co-trustees.
AMPX filed a notice under Rule 144 for a planned sale of company stock by an affiliate. The filing covers the proposed sale of 68,655 shares of common stock through broker Morgan Stanley Smith Barney LLC on the NYSE, with an indicated aggregate market value of 692,132. The company’s common shares outstanding are listed as 132,344,849 as of the figures in this notice.
The seller acquired 126,193 common shares on 11/20/2025 via a release of restricted stock units from the issuer as compensation. The notice also reports that during the past three months, Kang Sun sold 1,000,000 common shares on 11/17/2025 for gross proceeds of 10,595,300. By signing the notice, the seller represents that they are not aware of any undisclosed material adverse information about AMPX’s current or prospective operations.