---
schema_version: "secwatch.filing_event.v1"
accession: "0001437749-21-024533"
form_type: "8-K"
ticker: "MPWR"
cik: "0001280452"
company_name: "MONOLITHIC POWER SYSTEMS INC"
filed_at: "2021-10-28T23:59:59+00:00"
generated_at: "2026-06-28T16:37:42.912691+00:00"
event_type: "earnings"
sentiment: "positive"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# Monolithic Power Systems Q3 revenue $323.5M, +24.7% YoY; non-GAAP EPS $2.06

## Summary
- Revenue $323.5M (+10.3% QoQ, +24.7% YoY); GAAP EPS $1.44, non-GAAP EPS $2.06.
- GAAP gross margin 57.6% (incl $4M litigation benefit); non-GAAP gross margin 57.8%.
- Automotive revenue $54.4M (+91% YoY) and Industrial $52.2M (+70% YoY) led growth.
- Q4 guidance: revenue $314M-$326M; GAAP gross margin 56.0%-56.6%; non-GAAP 56.3%-56.9%.
- Stock-based comp expected $30.8M-$32.8M and litigation expense $3.5M-$3.9M in Q4.

## SEC filing metadata
- accession: 0001437749-21-024533
- form_type: 8-K
- ticker: MPWR
- cik: 0001280452
- company_name: MONOLITHIC POWER SYSTEMS INC
- filed_at: 2021-10-28T23:59:59+00:00
- event_type: earnings
- sentiment: positive
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 2.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1280452/000143774921024533/0001437749-21-024533-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1280452/000143774921024533/mpwr20211025_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001437749-21-024533
- JSON: https://secwatch.observer/filing/0001437749-21-024533.json
- Plain text: https://secwatch.observer/filing/0001437749-21-024533.txt

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