Form 4 for MPWR Monolithic Power Systems
Accepted 2026-04-01 18:41:09 ET · period of report 2026-03-30 · accession 0001214659-26-004185 · SEC index · Original document
Summary rows
Aggregated the way they appear in lists: one row per insider, transaction code and security table.
| X | Filed | Traded | Ticker | Insider | Title | Type | Price | Qty | Owned | ΔOwn | Value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| MT | 2026-04-01 18:41 | 2026-03-30 | MPWR | Tseng Saria | EVP, GC | S - Sale | $1,010.50 | -25.7K | 175.0K | -13% | -$25.94M |
Purchase Sale Sale after option exercise All abbreviations
Every reported transaction
| # | Table | Security | Date | Code | A/D | Shares | Price | Owned after | Own | Exercise / expiry | Underlying | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Common | Common Stock | 2026-03-30 | S | D | 5,154 | $1,000.81 | 195,502 | D | — | — | (F1) These transactions were made pursuant to a Rule 10b5-1 trading plan adopted on 11/28/2025. (F2) 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 $998.36 to $1,002.92. 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. (F3) Ending balance includes 30 shares acquired on February 17, 2026 through the Company's qualified ESPP program. |
| 2 | Common | Common Stock | 2026-03-30 | S | D | 9,080 | $1,005.18 | 186,422 | D | — | — | (F1) These transactions were made pursuant to a Rule 10b5-1 trading plan adopted on 11/28/2025. (F4) 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 $1,003.06 to $1,007.85. 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. |
| 3 | Common | Common Stock | 2026-03-30 | S | D | 3,360 | $1,009.63 | 183,062 | D | — | — | (F1) These transactions were made pursuant to a Rule 10b5-1 trading plan adopted on 11/28/2025. (F5) 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 $1,008.00 to $1,012.65. 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. |
| 4 | Common | Common Stock | 2026-03-30 | S | D | 3,194 | $1,017.22 | 179,868 | D | — | — | (F1) These transactions were made pursuant to a Rule 10b5-1 trading plan adopted on 11/28/2025. (F6) 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 $1,013.83 to $1,018.85. 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. |
| 5 | Common | Common Stock | 2026-03-30 | S | D | 2,200 | $1,023.00 | 177,668 | D | — | — | (F1) These transactions were made pursuant to a Rule 10b5-1 trading plan adopted on 11/28/2025. (F7) 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 $1,020.71 to $1,025.36. 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. |
| 6 | Common | Common Stock | 2026-03-30 | S | D | 2,440 | $1,029.21 | 175,228 | D | — | — | (F1) These transactions were made pursuant to a Rule 10b5-1 trading plan adopted on 11/28/2025. (F8) 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 $1,027.37 to $1,032.40. 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. |
| 7 | Common | Common Stock | 2026-03-30 | S | D | 166 | $1,035.60 | 175,062 | D | — | — | (F1) These transactions were made pursuant to a Rule 10b5-1 trading plan adopted on 11/28/2025. (F9) 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 $1,033.98 to $1,037.25. 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. |
| 8 | Common | Common Stock | 2026-03-30 | S | D | 80 | $1,041.12 | 174,982 | D | — | — | (F1) These transactions were made pursuant to a Rule 10b5-1 trading plan adopted on 11/28/2025. (F10) 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 $1,039.30 to $1,042.50. 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. |