Welcome to our dedicated page for Amprius Tech SEC filings (Ticker: AMPX), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
This page provides access to U.S. SEC filings for Amprius Technologies, Inc. (NYSE: AMPX), a manufacturer of high-energy and high-power lithium-ion batteries based on a Silicon Anode Platform. These regulatory documents offer detailed insight into the company’s operations, capital structure, executive changes, and financing activities.
Amprius uses current reports on Form 8-K to disclose material events. Recent 8-K filings describe the completion of an at-the-market equity offering program established under an At Market Issuance Sales Agreement, including the aggregate offering size and the resulting net proceeds. Other 8-Ks outline leadership transitions, such as the planned change in Chief Executive Officer, the appointment of a new Chief Financial Officer, and related employment and consulting arrangements, including salary, bonus eligibility, equity awards, and severance terms.
Investors and analysts can also use Amprius’ SEC filings to follow its periodic financial reporting. The company has filed 8-Ks to announce quarterly business and financial results and to furnish letters to shareholders discussing results for specific quarters. These filings complement the company’s earnings press releases and conference calls by providing formal disclosure under SEC rules.
On Stock Titan, AI-powered tools summarize lengthy filings so readers can quickly understand the key points in Amprius’ 10-K annual reports, 10-Q quarterly reports, and 8-K current reports, without needing to parse every technical detail. The platform also surfaces information related to equity compensation, executive employment agreements, and capital-raising activities. Real-time updates from EDGAR ensure that new filings, including any future Forms 4 reporting insider transactions, become available promptly with plain-language explanations to help users interpret their significance.
AMPX insider reported a proposed sale of 270,251 shares of Common stock on 03/12/2026. The filing lists the sale as resulting from an exercise of options under a registered plan for cash.
The filing also lists restricted stock vesting events of 17,895 shares (vested 06/09/2024) and 125,000 shares (vested 06/07/2025) as context for the position change.
AMPX reported proposed sales of Common Stock under registered plans. The filing lists 62,500 shares associated with restricted stock vesting on 06/07/2025 and 104,132 shares from an exercise of options on 03/10/2026, each described as "under a registered plan" and shown as sales by the issuer.
Amprius Technologies, Inc. reported that Chief Financial Officer Ricardo C. Rodriguez acquired 150,000 restricted stock units, each representing one share of common stock, at a price of $0.00 per unit. These units vest 1/16 starting on May 20, 2026 and quarterly thereafter until fully vested on February 20, 2030, subject to continued service. Following this award, he holds 350,000 restricted stock units in total.
Amprius Technologies, Inc. reported that Chief Executive Officer Thomas M. Stepien acquired 150,000 shares of common stock in the form of restricted stock units on March 4, 2026, at a price of $0.00 per share.
Each restricted stock unit represents the right to receive one share of common stock. According to the vesting schedule, 1/16 of the shares subject to the award will vest on May 20, 2026 and then quarterly on each August 20, November 20, February 20 and May 20, subject to his continued service, until the award is fully vested on February 20, 2030.
Following this grant, Stepien directly holds a total of 760,000 shares of common stock, which includes 750,000 restricted stock units that each represent a contingent right to receive one share, subject to their applicable vesting schedules and conditions.
Stefan Constantin Ionel reported acquisition or exercise transactions in this Form 4 filing.
Amprius Technologies, Inc. Chief Technology Officer Stefan Constantin Ionel reported an award of 110,000 shares of common stock in the form of restricted stock units at a price of $0.0000 per share. These RSUs vest 1/16 on May 20, 2026 and then quarterly on August 20, November 20, February 20 and May 20 until fully vested on February 20, 2030. Following this award, he directly holds 833,330 shares/units in total, including 643,440 restricted stock units subject to their respective vesting conditions.
Amprius Technologies, Inc. provides an overview of its silicon-anode lithium-ion battery business, focusing on high‑energy, fast‑charging cells for aviation, drones, HAPS, eVTOL and light electric vehicles. The company highlights over 500 customer engagements and more than 4.2 million battery cells shipped through December 31, 2025.
Amprius now relies heavily on its SiCore platform, produced via global contract manufacturers with access to over 2.0 GWh of annual capacity, while its Fremont facility is being expanded to a 10 MWh SiCore pilot line under a $14.8 million DIU contract. It recorded $19.1 million in impairment charges tied to terminating a large Brighton, Colorado factory lease and agreed to end that lease for a one‑time $20.0 million payment. The report also stresses concentration risk, noting one customer generated $27.1 million of 2025 revenue, and details extensive technology IP, regulatory exposure, and comprehensive risk factors.
Amprius Technologies reported very strong growth for 2025, with revenue rising 202% to $73.0 million and fourth-quarter revenue up 137% year over year to $25.2 million. Q4 gross margin improved to 24%, supporting the company’s first positive quarterly non-GAAP adjusted EBITDA of $1.8 million.
Full-year net loss was $44.0 million, including a $22.5 million impairment tied to a terminated Colorado facility; excluding this, adjusted net loss was $21.5 million and adjusted EBITDA was $(5.3) million. Management expects at least $125.0 million of revenue in 2026, net loss under $8.0 million, and at least $4.0 million of positive adjusted EBITDA, reflecting confidence in its contract manufacturing model and growing defense and aerospace demand.
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.