Transactions
5
Insider / MONOLITHIC POWER SYSTEMS INC
CHANG KUO WEI HERBERT
Director at MONOLITHIC POWER SYSTEMS INC
- Company
- MONOLITHIC POWER SYSTEMS INC
- Ticker
- MPWR
- First filing on record
- November 24, 2025
- Latest trade on record
- August 24, 2026
- SEC filings
- EDGAR ↗
CHANG KUO WEI HERBERT, Director at MONOLITHIC POWER SYSTEMS INC, has disclosed 5 transactions in MPWR since November 24, 2025: 0 purchases (0 open-market buys) and 4 sales, worth about $312K at the reported prices. The latest was filed August 25, 2026, 1 day after the trade.
Open-market buys
0
Sales
4
Avg. disclosure lag
1.6d
Trading in charts
Trade timeline
When does this person trade, how big, and in which direction? Every trade in the last 12 months.
Bought (above the line)Sold (below the line)Other transaction
In the last 12 months CHANG KUO WEI HERBERT made no purchases and 4 sales worth $312K, plus 1 other transaction. Dot size is the dollar amount.
Portfolio mix
Which stocks does this person trade most? Tile size is dollars traded, all time on record.
CHANG KUO WEI HERBERT has traded 1 stock on record; the largest by dollars is MPWR.
Reporting lag
Does this person report on time? One bar per filing against the Form 4 deadline.
On timeLate
0 of 5 filings on record were reported after the Form 4 deadline (two business days, counted here as 4 calendar days).
What kind of transactions
Most Form 4 rows are pay arriving or tax being withheld, not a decision to buy or sell. Only code P is an open-market purchase and code S an open-market sale. What each code means: Form 4 transaction codes.
| Code | Meaning | Rows | Shares | Value |
|---|---|---|---|---|
| S | Open-market sale | 4 | 300 | $312K |
| A | Grant or award | 1 | 189 | — |
| Year | Rows | Bought | Sold |
|---|---|---|---|
| 2026 | 3 | 0 | 2 · $135K |
| 2025 | 2 | 0 | 2 · $177K |
Transactions
| Security | Side | Trade date | Disclosed | Lag | Shares | Price | Value | Flags | Source | Share |
|---|---|---|---|---|---|---|---|---|---|---|
| MPWR | Sell S | August 24, 2026 | August 25, 2026 | 1d | 50 | $1,282 | $64K | Form 4 ↗ | ||
| MPWR | Sell S | August 11, 2026 | August 13, 2026 | 2d | 50 | $1,420 | $71K | Form 4 ↗ | ||
| MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 189 | — | — | Form 4 ↗ | ||
| MPWR | Sell S | November 25, 2025 | November 25, 2025 | 0d | 100 | $897 | $90K | Form 4 ↗ | ||
| MPWR | Sell S | November 21, 2025 | November 24, 2025 | 3d | 100 | $874 | $87K | Form 4 ↗ |
Filings
| Filed | Form | Accession | Rows | Status | Source |
|---|---|---|---|---|---|
| August 25, 2026 | Form 4 | 0001214659-26-010853 | 1 | published | EDGAR ↗ |
| August 13, 2026 | Form 4 | 0001214659-26-010101 | 1 | published | EDGAR ↗ |
| February 5, 2026 | Form 4 | 0001214659-26-001260 | 1 | published | EDGAR ↗ |
| November 25, 2025 | Form 4 | 0001214659-25-017235 | 1 | published | EDGAR ↗ |
| November 24, 2025 | Form 4 | 0001214659-25-017110 | 1 | published | EDGAR ↗ |
Other insiders at MONOLITHIC POWER SYSTEMS INC
- Hsing Michael CEO 93 rows
- BLEGEN THEODORE EVP and CFO 81 rows
- Tseng Saria EVP & General Counsel 74 rows
- Sciammas Maurice EVP, WW Sales & Marketing 71 rows
- Elmiger Eugen J Director 10 rows
- Lee Victor K Director 9 rows
- DEAN ROBERT W II Interim CFO 8 rows
- Xiao Deming EVP, Global Operations 8 rows
- Zhou Jeff Director 5 rows
- Wynne Eileen Director 2 rows
Everyone on file, with contracts and lobbying under the company's name: MONOLITHIC POWER SYSTEMS INC.
Guides for this page
- What is SEC Form 4? Who files: officers, directors and owners of more than 10% of a class of the company's shares.
- Form 4 transaction codes P = purchase. S = sale. These are the two market trades.
- Insider buying vs insider selling Selling outweighs buying by a wide margin in normal times.
- What disclosure data cannot tell you Filings are late by design: up to 45 days for Congress, two business days for insiders.
Sources and method
| Source | Filings | Rows | First filed | Newest filed | Read the originals |
|---|---|---|---|---|---|
| SEC EDGAR, Form 4 | 5 | 5 | November 24, 2025 | August 25, 2026 | Form 4 list on EDGAR |
Site built October 22, 2026. Every row in the tables above links to its own filing. To quote a figure, use the Cite button at the top of the page; see how to cite and reuse.
Every row comes from the reporting owner's Form 4 as filed with the SEC (EDGAR ownership XML), read daily. "Value" is shares × the reported price; code P is an open-market purchase, S a sale, M an option exercise, A a grant. The lag is the filing date minus the trade date; Form 4 is due within two business days. Amendments (4/A) are not merged. Details on the methodology page; report an error on corrections.
Not investment advice. Figures are public disclosures shown as filed; they may lag the trade and may be amended later. No recommendation is made or implied.