AMPX Stock: Insider Activity, Filings & Research
Amprius Technologies, Inc. (AMPX) — Drillr’s hub for AMPX insider activity, SEC filings, earnings signals and AI research. Over the trailing 3 months, AMPX insiders filed 0 open-market buys and 17 sales (SEC Form 4).
AMPX insider trading activity (SEC Form 4)
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| May 28, 2026 | Stefan Constantin Ionelofficer: Chief Technology Officer | Sell | 3,208 | $17.19 |
| May 28, 2026 | DIXON DONALD Rdirector | Sell | 17,895 | $17.90 |
| May 28, 2026 | Sun Kangdirector | Sell | 356 | $17.19 |
| May 28, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Sell | 4,375 | $17.19 |
| May 26, 2026 | Stefan Constantin Ionelofficer: Chief Technology Officer | Sell | 28,812 | $14.79 |
| May 26, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Sell | 60,702 | $14.79 |
| May 26, 2026 | Sun Kangdirector | Sell | 67,796 | $14.79 |
| May 7, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Grant | 200,000 | — |
| May 7, 2026 | Sun Kangdirector | Grant | 6,250 | — |
| Apr 2, 2026 | Sun Kangdirector | Option | 187,495 | $3.68 |
| Apr 2, 2026 | Sun Kangdirector | Sell | 249,037 | $16.78 |
| Apr 2, 2026 | Sun Kangdirector | Sell | 1,250,963 | $15.73 |
| Apr 2, 2026 | Sun Kangdirector | Option | 1,312,505 | $1.78 |
| Mar 24, 2026 | Sun Kangdirector | Sell | 65,046 | $19.06 |
| Mar 24, 2026 | Sun Kangdirector | Sell | 152,823 | $18.69 |
Source: AMPX SEC Form 4 filings, latest May 28, 2026. For informational purposes only — not investment advice.
Amprius Technologies, Inc. company profile
Overview
Amprius Technologies, Inc. (NYSE:AMPX) is a California-based battery manufacturer founded in 2008 that specializes in advanced lithium-ion batteries using proprietary silicon nanowire anode technology. The company went public in September 2022 and has positioned itself as a premium battery supplier primarily serving the aerospace, defense, and electric vehicle industries. Amprius operates manufacturing facilities in Fremont, California, and has been developing additional production capacity through contract manufacturing partnerships globally.
Business
Amprius Technologies operates in the advanced battery manufacturing industry, specifically focusing on lithium-ion batteries with silicon nanowire anode technology. Traditional lithium-ion batteries use graphite anodes, but Amprius has developed a proprietary approach using silicon nanowires that enables significantly higher energy density - the amount of energy that can be stored per unit of weight or volume. The company's core product offering centers around its **SiCore** battery platform, which delivers energy densities of up to 500 watt-hours per kilogram (Wh/kg) compared to conventional lithium-ion batteries that typically achieve 150-250 Wh/kg. This dramatic improvement in energy density means devices can run longer on the same battery weight, or achieve the same runtime with much lighter batteries - a critical advantage in aerospace and defense applications where weight is paramount. Amprius manufactures batteries in multiple form factors including cylindrical cells (similar to AA batteries but larger), pouch cells (flat, flexible packages), and custom configurations. The company offers 14 different standard products (SKUs) and serves three primary market segments: 1. **Aerospace and Defense** (approximately 75% of revenue): This includes batteries for drones, unmanned aircraft systems, military equipment, and aviation applications where high energy density and reliability are crucial. 2. **Light Electric Vehicles** (approximately 25% of revenue): This segment includes electric bikes, scooters, and other small electric vehicles where lighter weight batteries can significantly improve performance and range. 3. **Development Services**: The company also provides custom battery development and testing services, though this represents a small portion of total revenue. The battery industry is highly technical, with customers typically requiring 9-18 months to qualify new battery technologies before incorporating them into their products. This lengthy qualification process reflects the critical nature of battery performance in applications where failure could be catastrophic.
Revenue model
Amprius generates revenue primarily through direct product sales of its silicon nanowire lithium-ion batteries, with some additional income from development services and government grants. The company's customers are primarily original equipment manufacturers (OEMs) in aerospace, defense, and electric vehicle industries who integrate Amprius batteries into their final products. The business model is built on commanding premium pricing due to the superior performance characteristics of its silicon nanowire technology. While conventional lithium-ion batteries might sell for $100-200 per kWh, Amprius can charge significantly higher prices because its batteries deliver 2-3 times the energy density, enabling customers to create products that would be impossible with standard battery technology. Revenue growth depends heavily on customer qualification cycles, which typically take 9-18 months as customers must thoroughly test and validate new battery technologies before incorporating them into production. Once qualified, customers often place substantial orders - the company has secured individual contracts worth $10-50 million and has signed agreements with Fortune 500 companies. Several factors could impact Amprius's margins and profitability. **Positive factors** include the company's technological differentiation allowing premium pricing, the growing demand for high-performance batteries in aerospace and electric vehicle applications, and the potential for economies of scale as production volumes increase. The company's focus on high-value applications where performance matters more than cost also supports pricing power. **Negative factors** include intense competition from established battery manufacturers, particularly Chinese companies with significant scale advantages and lower cost structures. Manufacturing costs remain high due to the specialized silicon nanowire production process and relatively low volumes. The company currently operates with negative gross margins, indicating that manufacturing costs exceed selling prices. Additionally, potential trade tensions and tariffs could impact the company's manufacturing strategy, as it currently relies on contract manufacturing in China while exploring diversification to Korea and Europe. The lengthy customer qualification process also creates revenue lumpiness and makes growth difficult to predict, while the capital-intensive nature of battery manufacturing requires substantial ongoing investment in production capacity.
Competitive moat
Amprius's competitive moat centers on its proprietary silicon nanowire anode technology, which represents a meaningful technological differentiation in the battery industry. The company's ability to achieve 500 Wh/kg energy density - roughly double that of conventional lithium-ion batteries - creates a substantial performance advantage that is difficult for competitors to replicate quickly. The strength of this moat is moderate but faces significant challenges. On the positive side, Amprius has been developing this technology since 2008, accumulating substantial intellectual property and manufacturing know-how. The silicon nanowire approach requires specialized production techniques and equipment, creating some barriers to entry. The company's focus on high-performance applications where customers prioritize performance over cost also provides some protection from price-based competition. However, the moat faces several vulnerabilities. The battery industry is characterized by rapid technological advancement and massive investment from well-funded competitors, particularly Chinese battery giants like CATL and BYD who have substantially greater resources and manufacturing scale. These companies are actively developing their own advanced battery technologies and could potentially close the performance gap over time. Additionally, Amprius's current reliance on contract manufacturing limits its control over production costs and capacity, potentially weakening its competitive position. The company's small scale compared to industry leaders also means it lacks the economies of scale necessary to compete on cost, limiting its addressable market to applications where performance justifies premium pricing. The regulatory environment and potential trade restrictions could also impact the company's manufacturing strategy and cost structure. While Amprius has technological advantages today, the sustainability of this moat depends on continued innovation and the company's ability to scale production while maintaining its performance edge against much larger, better-funded competitors.
Risks & safety
Amprius presents a mixed margin of safety profile with both strengths and significant risks. **Liquidity and Solvency:** - Strong cash position: $48.4 million in cash with no debt as of Q1 2025 - Healthy current ratio of 4.74, indicating strong short-term liquidity - Current cash burn rate of approximately $15 million per quarter in free cash flow - At current burn rate, cash runway extends roughly 3-4 quarters without additional funding **Valuation Metrics:** - Trading at negative P/E ratios due to losses, making traditional valuation difficult - Price-to-book ratio of 4.49 suggests premium valuation relative to tangible assets - EV/EBITDA of -8.75 (negative due to losses) - Graham net-net ratio of 0.086, indicating stock trades below liquidation value **Other Considerations:** - Revenue growing rapidly (383% year-over-year in Q1 2025) but from small base - Negative gross margins indicate fundamental profitability challenges - High customer concentration risk with lumpy revenue patterns - Early-stage company in capital-intensive industry requiring ongoing investment
Recent development
Over the past few years, Amprius has undergone significant strategic evolution focused on scaling production, diversifying manufacturing, and expanding its customer base. The company has dramatically increased its manufacturing capacity from minimal production in 2022 to over 1.8 gigawatt-hours annually by 2024, primarily through partnerships with contract manufacturers in Asia. A key strategic pivot has been the expansion beyond its original aerospace and defense focus into light electric vehicles, which now represents approximately 25% of revenue. The company has also broadened its product portfolio from a few specialized offerings to 14 standard SKUs across different form factors, reducing customization requirements and enabling faster customer adoption. Geographically, Amprius has pursued manufacturing diversification to reduce dependence on Chinese contract manufacturers, establishing partnerships in Korea and exploring European options. This shift reflects both supply chain risk management and potential trade policy considerations. The company has achieved several significant technology milestones, including the development of 500 Wh/kg battery platforms and the launch of its SiCore product family. Recent innovations include 370 Wh/kg high-power pouch cells and 6,300 milliamp-hour cylindrical cells, demonstrating continued advancement in energy density and power capabilities. Customer expansion has been substantial, growing from serving dozens of customers to over 235 customers in 2024, with approximately 77% of revenue now coming from outside the United States. The company has secured major contracts including a $20 million agreement for light electric vehicle applications and partnerships with Fortune 500 companies, indicating growing market acceptance of its technology.
AMPX company profile · for informational purposes only — not investment advice.
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