Saria Tseng - 15 Oct 2025 Form 4 Insider Report for MONOLITHIC POWER SYSTEMS INC (MPWR)

Signature
/s/ Saria Tseng
Issuer symbol
MPWR
Transactions as of
15 Oct 2025
Net transactions value
-$17,139,295
Form type
4
Filing time
17 Oct 2025, 12:11:43 UTC
Previous filing
23 Sep 2025
Next filing
24 Oct 2025

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Tseng Saria EVP & General Counsel 5808 LAKE WASHINGTON BLVD NE, KIRKLAND /s/ Saria Tseng 16 Oct 2025 0001312593

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction MPWR Common Stock Sale $14,254,973 -14,028 -9.7% $1016.18 130,466 15 Oct 2025 Direct F1
transaction MPWR Common Stock Sale $1,530,869 -1,499 -1.1% $1021.26 128,967 16 Oct 2025 Direct F1
transaction MPWR Common Stock Sale $1,353,454 -1,313 -1% $1030.81 127,654 16 Oct 2025 Direct F1
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Buy Plan / Sale Plan: These are also open market purchases/sales of shares, but in this case the transaction is part of a trading plan. Rule 10b5-1 allows insiders to setup a trading plan to buy/sell stocks over a certain period of time. Since the purchases/sales are predetermined, this protects the insiders from violating insider trading law.

Transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c).

Explanation of Responses:

Id Content
F1 These transactions were made pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on 8/30/2024.