---
schema_version: "secwatch.filing_event.v1"
accession: "0001899287-25-000048"
form_type: "8-K"
ticker: "AMPX"
cik: "0001899287"
company_name: "Amprius Technologies, Inc."
filed_at: "2025-12-22T23:59:59+00:00"
generated_at: "2026-05-16T12:27:52.304505+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# Amprius CEO Kang Sun steps down Dec 31; President Tom Stepien appointed CEO effective Jan 1, 2026

## Summary
- CEO Kang Sun to step down effective Dec 31, 2025; remains on Board as Executive Advisor from Jan 1, 2026.
- New employment agreement for Sun: $633k annual salary, no annual bonus, eligible for equity vesting, severance of 6 months base salary.
- President Tom Stepien appointed CEO effective Jan 1, 2026; receives $633k base salary, target bonus 100% of base.
- Stepien granted 200,000 RSUs vesting 25% at 1-year anniversary, remainder quarterly over 3 years.
- Stepien previously CEO of South 8 Technologies and Operating Partner at KCK Group; transition not due to disagreement.

## SEC filing metadata
- accession: 0001899287-25-000048
- form_type: 8-K
- ticker: AMPX
- cik: 0001899287
- company_name: Amprius Technologies, Inc.
- filed_at: 2025-12-22T23:59:59+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 5.02
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1899287/000189928725000048/0001899287-25-000048-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1899287/000189928725000048/ampx-20251218.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001899287-25-000048
- JSON: https://secwatch.observer/filing/0001899287-25-000048.json
- Plain text: https://secwatch.observer/filing/0001899287-25-000048.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.