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Amprius Technologies, Inc. (AMPX) director Sun Kang reported a sale of 62,101 shares of common stock on August 21, 2026. The transaction was effected pursuant to non-discretionary, issuer-mandated sell-to-cover arrangements to fund tax withholding obligations upon vesting of restricted stock units. The average execution price was $10.341 per share, with actual sale prices ranging from $10.10 to $10.48. Following this transaction, Kang directly held 1,218,397 shares, including 911,688 restricted stock units, and indirectly held 56,406 shares through the KANG & CECILLIA SUN FAMILY REVOCABLE TRUST, for which he and his spouse are co-trustees.
Amprius Technologies, Inc. (AMPX) received a notice that director Kang Sun intends to sell company common stock under Rule 144. The planned sale relates to 126,974 shares expected from the release of restricted stock units on 08/20/2026, with the stated purpose of covering withholding taxes upon vesting.
Morgan Stanley Smith Barney LLC is listed as the broker. The notice also lists a prior Rule 10b5-1 sale of 356 shares of common stock on 05/27/2026 for $6,120.89 during the past three months.
Amprius Technologies, Inc. (AMPX) reported that Chief Technology Officer Stefan Constantin Ionel sold 29,681 shares of common stock on 2026-08-21 at an average price of $10.341 per share. The sale was a non-discretionary sell-to-cover mandated by the company to fund tax withholding on vested restricted stock units. After the transaction, Ionel directly held 771,629 shares of common stock, including 525,176 restricted stock units, each RSU representing a contingent right to receive one share, subject to vesting conditions.
Amprius Technologies, Inc. (symbol AMPX) has an affiliate, officer Constantin Ionel Stefan, filing a notice of proposed sale of restricted securities under Rule 144. The notice contemplates the potential sale of up to 29,681 shares of Amprius common stock through Morgan Stanley Smith Barney LLC, with an aggregate market value of $306,930.27 as of the filing details. These shares relate to the 08/20/2026 release of 59,132 restricted stock units received from the issuer as compensation, and the filer states the shares are to be sold to cover withholding taxes upon vesting. Over the prior three months, the filer reported a sale of 3,208 shares of common stock on 05/27/2026 for $55,156.75.
Amprius Technologies, Inc. (AMPX) reported insider activity by Chief Executive Officer and director Thomas M. Stepien involving sales, gifts, and a transfer of common stock. On August 21, 2026 he sold 23,529 shares at an average of $10.341 per share in multiple trades between $10.10 and $10.48, in a non‑discretionary, issuer‑mandated sell‑to‑cover arrangement for tax withholding tied to restricted stock unit vesting. On August 24, 2026 he sold an additional 8,000 shares at $10.03 per share. On August 25, 2026 he made bona fide gifts totaling 15,346 shares, including 346 shares transferred to the Rogers Stepien Family Revocable Trust. The same 346 shares were recorded as an indirect acquisition by that trust, which held 37,260 shares after the transfer. Reported holdings include 568,750 restricted stock units, each convertible into one share upon vesting.
Amprius Technologies, Inc. (AMPX) received a notice under Rule 144 from Thomas M. Stepien for a proposed sale of its common stock. The notice lists a planned sale of 23,529 shares of common stock through Morgan Stanley Smith Barney LLC, with an aggregate market value of $243,312.64 as of the notice. The sale relates to the release of 46,875 restricted stock units on 08/20/2026, with the filer stating the shares are to be sold to cover withholding taxes upon vesting of these awards. The notice also reports prior sales in the past three months, including 4,375 shares on 05/27/2026, 2,000 shares on 06/04/2026, and 8,000 shares on 08/24/2026.
Amprius Technologies, Inc. (symbol AMPX) is named as the issuer in a notice filed by insider Thomas M. Stepien to sell company common stock under Rule 144. The planned transaction involves 8,000 shares of common stock held at Morgan Stanley Smith Barney LLC, relating to restricted stock that vests on August 20, 2026 under a registered plan, with the issuer listed as Amprius and the consideration described as services rendered.
Over the prior three months, Thomas M. Stepien reported additional sales of Amprius common stock: 23,529 shares for $243,312.64 on August 20, 2026; 2,000 shares for $41,940.00 on June 4, 2026; and 4,375 shares for $75,221.56 on May 27, 2026.
Amprius Technologies, Inc. entered into a Second Amendment to its Industrial Lease Agreement for its facility at 1000-1180 Page Avenue, Fremont, California, with Los Altos Fields, LLC. The amendment extends the lease term, previously ending June 30, 2027, by 84 months, from July 1, 2027 through June 30, 2034.
The company receives two additional five-year extension options, subject to existing lease terms. Base rent during the extended term will escalate annually under a specified rent schedule, and Amprius will continue paying its percentage share of operating expenses. Total future lease payments under the amended lease are expected to be approximately $10.5 million.
Amprius Technologies, Inc. is reported to have 4,713,803 shares of its common stock beneficially owned by Jane Street Group, LLC and its subsidiaries on a Schedule 13G/A Amendment No. 1. This represents 3.3% of the outstanding common stock, placing the group below the 5% reporting threshold.
The filing states that Jane Street has no sole voting or dispositive power over these shares, but holds shared voting and dispositive power over all 4,713,803 shares through subsidiaries Jane Street Capital, LLC and Jane Street Global Trading, LLC, each organized in Delaware.
Amprius Technologies, Inc. delivered rapid growth for the quarter ended June 30, 2026. Revenue rose to $34.0 million from $15.1 million a year earlier, driven mainly by SiCore lithium‑ion battery sales, and gross margin improved to 27% from 9%. Operating loss narrowed to $4.3 million and net loss to $3.2 million, versus $6.4 million in the prior-year quarter.
For the first six months of 2026, revenue reached $62.6 million, up from $26.4 million, with net loss improving to $8.2 million. Cash and cash equivalents were $74.5 million at June 30, 2026, but operating activities used $40.1 million of cash, including a $20.0 million payment to terminate the Brighton, Colorado factory lease as the company pivots to contract manufacturing with access to over 2.0 GWh of external SiCore capacity and expands its Fremont pilot line. An $18.1 million Defense Innovation Unit contract supports this expansion, with $1.5 million recognized year‑to‑date. Key risks include dependence on defense-related customers (notably Ukraine), geopolitical and trade uncertainties, potential Chinese export controls on battery materials, and continued operating losses that may require additional capital.