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Amprius Technologies, Inc. filings document operating results, material events, governance matters and capital-structure disclosures for a public battery technology company. Its 8-K reports include quarterly and annual financial-result releases, material agreement updates, auditor changes, lease-related matters, and equity offering activity.
Amprius disclosure records also cover proxy and shareholder voting matters, emerging growth company status, common stock, redeemable warrants, and board and executive compensation topics. These filings provide the formal record for the company's silicon-anode battery business, security structure, financing activity, risk disclosures and corporate governance practices.
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.
AMPX filing: Notice of proposed sales of Common Stock reported on Form 144. The filing lists broker information for Morgan Stanley Smith Barney LLC and records a release of restricted stock units dated 05/20/2026. It also itemizes multiple 10b5-1 sales attributed to KANG SUN on 03/23/2026, 04/01/2026, and 05/21/2026, with per‑trade share counts and gross proceeds shown in the excerpt.
Amprius Technologies, Inc. Chief Executive Officer Thomas M. Stepien reported an open-market sale of 4,375 shares of common stock at an average price of $17.1935 per share. According to the disclosure, this was a non-discretionary sell-to-cover transaction mandated by the company to fund tax withholding tied to vesting restricted stock units. After the sale, Stepien directly holds 694,923 shares, which the filing notes include 615,625 restricted stock units that may convert into common shares as their vesting conditions are met.
AMPX filed a Form 144 reporting an intended sale and recent dispositions of Common Stock. The filing lists 9,375 shares to be sold following a "Release of restricted stock units" on 05/20/2026. It also discloses 60,702 shares sold on 05/21/2026 for $897,685.46.
Amprius Technologies, Inc. Chief Technology Officer Stefan Constantin Ionel reported an open-market sale of 3,208 shares of common stock at an average price of $17.1935 per share. The sale was executed under non-discretionary, sell-to-cover arrangements mandated by the company to fund tax withholding on vested restricted stock units.
Following this tax-related sale, Ionel beneficially owns 801,310 shares, including 584,308 restricted stock units that each represent the right to receive one share of common stock, subject to vesting conditions.
Constantin Ionel Stefan submitted a Form 144 reporting a proposed sale related to a release of 6,875 restricted stock units dated 05/20/2026. The filing also records 28,812 shares sold during the prior three months on 05/21/2026 for $426,083.38. Morgan Stanley Smith Barney LLC is listed as the broker.
Amprius Technologies director Donald R. Dixon reported an open‑market sale of 17,895 shares of common stock indirectly held through an affiliated entity at $17.8962 per share. After this sale, one indirect position shown holds 484,380 shares, alongside 269,656 shares held directly and another 163,142 shares held indirectly.
Footnotes state that certain indirect holdings are in The Dixon Revocable Trust and the Donald & Elizabeth Dixon 2004 Family Partners, where Dixon is a co‑trustee or co‑general partner. The direct position includes 44,444 restricted stock units that may convert into common shares if vesting conditions are met.
Amprius Technologies director Sun Kang reported an open-market sale of 67,796 shares of common stock on May 21, 2026 at an average price of $14.7884 per share. According to the disclosure, this sale was executed under non-discretionary, sell-to-cover arrangements mandated by the company to fund tax withholding obligations tied to the vesting of restricted stock units.
Following the sale, Kang directly held 1,280,854 common shares, which the filing notes include 1,039,443 restricted stock units, each representing a contingent right to one share subject to vesting conditions. Separately, 56,406 shares are held indirectly through the KANG & CECILLIA SUN FAMILY REVOCABLE TRUST, for which Kang and his spouse serve as co-trustees.
AMPX submitted a Form 144 notice reporting proposed and recent sales of Common Stock by an affiliate, including planned sales under 10b5-1 and a release of restricted stock units. The filing lists multiple 10b5-1 sale transactions on 03/23/2026 and 04/01/2026
The excerpt shows 10b5-1 sales of 152,823, 65,046, 1,250,963, and 249,037 shares on the dates above with aggregate proceeds reported as currency amounts. It also records a release of 126,192 RSUs on 05/20/2026 tied to compensation.
Amprius Technologies, Inc. Chief Technology Officer Stefan Constantin Ionel reported an open-market sale of 28,812 shares of common stock on May 21, 2026 at an average price of $14.7884 per share. According to the disclosure, this sale was a non-discretionary, sell-to-cover transaction mandated by the company to fund tax withholding obligations related to vesting restricted stock units. After the sale, Ionel directly held 804,518 shares of common stock, including 591,183 restricted stock units that may convert into shares as vesting conditions are met.