Insider trade

CFO sold ~$172K of MPWR shares in the open market

Traded Nov 3, 2025 · Filed Nov 5, 2025

~$172K
Approx. value · 168 sh @ $1,021.28: 76K
Holds after · shares reported: +47.4%
stock since the trade · S&P 500 +13.4%, $1,003.93 → $1,479.89 on Oct 5

Why it stands out

The CFO of Monolithic Power Systems sold $172K of Monolithic Power Systems shares. The filing says it was made under a pre-arranged trading plan.

Written from the filing's own figures. OQRO describes what was reported and never tells you what to buy or sell

View the official recordSEC Form 4 — Statement of Changes in Beneficial Ownership

All the details

Dates, kept separate

Transaction date: Nov 3, 2025
Reporting period: Not applicable
Filed with the SEC: Nov 5, 2025

CFO$100K–$500KPre-arranged plan referenced

Context

Classification

open market sale

Code S — open-market or private sale

Absolute commitment

~$171,575

Shares × reported transaction price

Timing vs results

4 days after results of Oct 30, 2025, 94 days before results of Feb 5, 2026

Results dates are the company's own 8-K (Item 2.02). Many companies only let insiders trade in a window after results

Price at the time

Closed at $1,003.93 on Nov 3, 2025, 121% above its 52-week low and 9% below its high, after a 9% rise over the previous 30 trading days

52-week range $455.19 (Apr 8, 2025) to $1,105.05 (Oct 27, 2025), 84% of the way up, from 250 adjusted closes. 30 trading days earlier: $922.81 on Sep 22, 2025. Describes the past only, not a forecast

Planned / mechanical clue

Footnote references a pre-arranged trading plan (Rule 10b5-1)

Only flagged when a footnote says so; never inferred

Securities lawsuit open at the trade date

A securities lawsuit naming the company as a defendant was filed on Feb 4, 2025 in the U.S. District Court, W.D. Washington. A filing is an allegation, not a finding.

Waterford Township General Employees Retirement System v. Monolithic Power Systems Inc, docket 2:25-cv-00220, via CourtListener (court records). Nature of suit 850, company named as first defendant

After it was reported

After	Stock	S&P 500	Difference
7 days	−4.2%	+0.9%	−5.0%
30 days	−3.7%	+1.2%	−4.9%
90 days	+16.5%	+1.8%	+14.7%
180 days	+57.3%	+6.0%	+51.3%

Past results only. Not a forecast.

Source receipt

Record ID: 0001214659-25-015933
Filed / recorded: Nov 5, 2025, 12:31 AM UTC
Added to OQRO: Oct 2, 2026, 12:28 PM UTC
Parser: form4-xml-v1
Data quality: Verified: identifiers matched exactly
Issuer: MONOLITHIC POWER SYSTEMS INC
Issuer CIK: 1280452
Ticker: MPWR
Reporting person: Theodore Blegen
Relationship: Officer
Officer title: EVP and CFO
Security: Common Stock
Table: Non-derivative (Table I)
Transaction date: Nov 3, 2025
Transaction code: S
Shares / units: 168
Price per share: $1,021.28
Acquired / disposed: Disposed (D)
Shares owned after: 76,218
Ownership form: Direct
Amendment: No

Footnotes from the filing

These transactions were made pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on 2/26/2025.
The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $1,021.04 to $1,021.32. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

Around the same time

Theodore Blegen (EVP and CFO) sold ~$36K of Monolithic Power Systems

Scheduled in advanceFiled 10mo ago

Theodore Blegen (EVP and CFO) sold ~$36K of Monolithic Power Systems

Scheduled in advanceFiled 10mo ago

Theodore Blegen (EVP and CFO) sold ~$72K of Monolithic Power Systems

Scheduled in advanceFiled 10mo ago