Insider trade

Officer sold ~$312K of MPWR shares in the open market

Traded Nov 25, 2025 · Filed Nov 28, 2025

~$312K
Reported value · 346 sh @ $900.41: 202K
Holds after · shares reported: +62.9%
stock since the trade · S&P 500 +14.8%, $908.61 → $1,479.89 on Oct 5

Why it stands out

Monolithic Power Systems's & General Counsel sold $312K of Monolithic Power Systems shares. Nobody planned it ahead of time.

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 25, 2025
Reporting period: Not applicable
Filed with the SEC: Nov 28, 2025

Officer$100K–$500K

Context

Classification

open market sale

Code S — open-market or private sale

Absolute commitment

~$311,542

Shares × reported transaction price

Timing vs results

26 days after results of Oct 30, 2025, 72 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 $908.61 on Nov 25, 2025, 100% above its 52-week low and 18% below its high, after a 6% drop over the previous 30 trading days

52-week range $455.19 (Apr 8, 2025) to $1,105.05 (Oct 27, 2025), 70% of the way up, from 250 adjusted closes. 30 trading days earlier: $968.25 on Oct 14, 2025. Describes the past only, not a forecast

Planned / mechanical clue

None found in footnotes

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	+6.0%	+0.5%	+5.5%
30 days	-2.4%	+0.2%	-2.6%
90 days	+23.1%	+0.9%	+22.2%
180 days	+66.1%	+11.5%	+54.6%

Past results only. Not a forecast.

Source receipt

Record ID: 0001214659-25-017303
Filed / recorded: Nov 28, 2025, 3:15 PM 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: Saria Tseng
Relationship: Officer
Officer title: EVP & General Counsel
Security: Common Stock
Table: Non-derivative (Table I)
Transaction date: Nov 25, 2025
Transaction code: S
Shares / units: 346
Price per share: $900.41
Acquired / disposed: Disposed (D)
Shares owned after: 201,690
Ownership form: Direct
Amendment: No

Footnotes from the filing

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 $900.02 to $900.90. 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

10mo ago

12KShares

Gift or transfer — classified separately from trades.

Why it stands out Official record

CFO sold ~$36K of Monolithic Power Systems

Scheduled in advance10mo ago

CFO sold ~$36K of Monolithic Power Systems

Scheduled in advance10mo ago