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Amprius Technologies, Inc. reports its Annual Report on Form 10-K for the fiscal year ended December 31, 2025. The company describes commercial production and customer validation for its silicon-anode batteries, noting over 4.2 million battery cells shipped through December 31, 2025 and more than 500 customer engagements since inception. It reports access to annual SiCore production exceeding 2.0 GWh via contract manufacturers, shipped SiMaxx from its Fremont facility, and plans to expand a pilot SiCore line to 10 MWh. Financial and operational items include a $14.8M DIU contract, $19.1M impairment charges related to a Colorado lease, and a $20.0M lease-termination payment agreed on January 30, 2026. The filing highlights intellectual property (86 patents) and ongoing risks tied to scale-up, supply-chain reliance, NDAA compliance, and safety testing.
Amprius Technologies, Inc. will hold its 2026 annual stockholder meeting virtually on June 11, 2026 at 10:00 a.m. local time. Stockholders will vote on electing two Class I directors, Kathleen Bayless and CEO Thomas M. Stepien, to serve until the 2029 meeting, and on ratifying Deloitte & Touche LLP as independent registered public accounting firm for the year ending December 31, 2026.
The record date is April 13, 2026, with 140,807,061 common shares entitled to one vote each. The proxy describes the company’s staggered, majority-independent board, the planned retirement of director Wen Hsieh, committee structures, director pay, and 2025 compensation for key executives including Stepien, CFO Ricardo C. Rodriguez, and Executive Advisor Kang Sun. It also explains the recent transition of auditor from BDO USA, P.C. to Deloitte.
Jane Street Group, LLC reports shared beneficial ownership of 7,014,784 shares (5.1%) of Amprius Technologies, Inc. The filing shows shared voting and dispositive power over those shares. Subsidiaries listed include Jane Street Capital, LLC (3,780,489 shares, 2.8%) and Jane Street Global Trading, LLC (3,234,295 shares, 2.4%).
The disclosure is a Schedule 13G ownership filing dated 04/28/2026, signed by Jeremy Kahn as authorized signatory.
Amprius Technologies, Inc. is changing its independent auditor. The audit committee approved the engagement of Deloitte & Touche LLP to audit the company’s consolidated financial statements for the year ending December 31, 2026, effective April 21, 2026.
On April 17, 2026, the audit committee dismissed BDO USA, P.C., which had audited the company for the years ended December 31, 2025 and 2024. BDO’s prior reports did not contain adverse or disclaimed opinions and were not qualified or modified as to audit scope or accounting principles, and the company states there were no disagreements and no reportable events under Regulation S-K Item 304.
Amprius Technologies director Sun Kang exercised stock options and sold shares in a pre-planned trade. On April 1, 2026, he exercised options for a total of 1,500,000 shares of common stock at strike prices of $1.78 and $3.68 per share, then sold 1,500,000 shares in open-market transactions at average prices of $15.7328 and $16.7829, with actual sale prices ranging from $15.37 to $17.31.
Following these transactions, he holds 1,342,400 shares directly and 56,406 shares indirectly through the KANG & CECILLIA SUN FAMILY REVOCABLE TRUST. His holdings also include 1,159,385 restricted stock units, each representing a contingent right to one share. All reported trades were executed under a Rule 10b5-1 trading plan adopted on August 18, 2025, indicating they were pre-scheduled rather than discretionary.
Morgan Stanley Smith Barney LLC Executive Financial Services filed a Form 144 notifying the proposed sale of 1,500,000 shares of Common stock to be sold on 04/01/2026 pursuant to an exercise of stock options for cash. The filing also lists recent 10b5-1 dispositions by KANG SUN during Jan–Mar 2026, including sales of 950,548 and 506,267 shares on 01/16/2026 and 01/12/2026 respectively.
The Vanguard Group amended a Schedule 13G filing to report zero beneficial ownership of Amprius Technologies, Inc. common stock. The amendment follows an internal realignment effective January 12, 2026 under SEC Release No. 34-39538 and states certain Vanguard subsidiaries will report separately.
The filing lists Amount beneficially owned: 0 and Percent of class: 0%, and confirms no sole or shared voting or dispositive power over Amprius shares. The filing is signed by Ashley Grim on 03/26/2026.
Amprius Technologies director Sun Kang, through the KANG & CECILLIA SUN FAMILY REVOCABLE TRUST, reported open-market sales of a total of 217,869 shares of common stock on March 23, 2026. The shares were sold in two tranches at average prices of $18.6863 and $19.0589, with individual trade prices ranging from $17.89 to $19.36. These transactions were executed under a pre-arranged Rule 10b5-1 trading plan adopted on August 18, 2025. Following the sales, the trust held 56,406 shares indirectly, while Kang also held 1,342,400 shares directly, including 1,159,385 restricted stock units subject to vesting conditions.
AMPX notice of proposed sale: 192,727 shares of Common stock (listed as Restricted Stock Units) are presented for resale. The filing lists multiple 10b5-1 sales by KANG SUN, including sales of 950,548, 506,267, 61,251, and 43,185 shares on various dates in January–February 2026.
Transactions are reported as 10b5-1 plan sales; cash‑flow treatment and further qualifiers are those shown in the excerpt.
RODRIGUEZ RICARDO C. reported acquisition or exercise transactions in this Form 4 filing.
Amprius Technologies, Inc. reported that its Chief Financial Officer, Ricardo C. Rodriguez, received a grant of 150,000 shares of common stock on March 4, 2026 at a price of $0.00 per share. Following this equity award, he directly owns 350,000 shares.
This amended filing corrects the vesting schedule for the previously reported restricted stock units. According to the updated terms, 3/16 of the shares will vest on November 20, 2026, with additional portions vesting quarterly on February 20, May 20, August 20 and November 20 until the award is fully vested on February 20, 2030, subject to his continued service.