Maurice Sciammas - 19 Nov 2025 Form 4 Insider Report for MONOLITHIC POWER SYSTEMS INC (MPWR)

Signature
/s/ Saria Tseng, attorney-in-fact for Mr. Maurice Sciammas
Issuer symbol
MPWR
Transactions as of
19 Nov 2025
Transactions value $
-$6,121,059
Form type
4
Filing time
20 Nov 2025, 16:47:14 UTC
Previous filing
14 Nov 2025
Next filing
25 Nov 2025

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Sciammas Maurice EVP, WW Sales & Marketing 1555 PALM BEACH LAKES BLVD., WEST PALM BEACH /s/ Saria Tseng, attorney-in-fact for Mr. Maurice Sciammas 19 Nov 2025 0001360833

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction MPWR Common Stock Sale -$207K -240 -0.13% $862.58 183K 19 Nov 2025 Direct F1
transaction MPWR Common Stock Sale -$138K -160 -0.09% $863.86 183K 19 Nov 2025 Direct
transaction MPWR Common Stock Sale -$34.6K -40 -0.02% $865.89 183K 19 Nov 2025 Direct
transaction MPWR Common Stock Sale -$294K -339 -0.19% $866.19 183K 19 Nov 2025 Direct F2
transaction MPWR Common Stock Sale -$606K -699 -0.38% $867.57 182K 19 Nov 2025 Direct F3
transaction MPWR Common Stock Sale -$628K -723 -0.4% $868.42 181K 19 Nov 2025 Direct F4
transaction MPWR Common Stock Sale -$1.6M -1.84K -1.02% $869.39 179K 19 Nov 2025 Direct F5
transaction MPWR Common Stock Sale -$279K -320 -0.18% $870.36 179K 19 Nov 2025 Direct F6
transaction MPWR Common Stock Sale -$192K -220 -0.12% $871.45 179K 19 Nov 2025 Direct F7
transaction MPWR Common Stock Sale -$501K -574 -0.32% $872.80 178K 19 Nov 2025 Direct F8
transaction MPWR Common Stock Sale -$1M -1.15K -0.64% $873.78 177K 19 Nov 2025 Direct F9
transaction MPWR Common Stock Sale -$639K -731 -0.41% $874.50 176K 19 Nov 2025 Direct F10
holding MPWR Common Stock 1.7K 19 Nov 2025 The Joseph Roger Sciammas 2020 Irrevocable Trust
holding MPWR Common Stock 2K 19 Nov 2025 Rosalind Sciammas Family 2021 Trust
holding MPWR Common Stock 1.3K 19 Nov 2025 Rosalind Sciammas Brokerage Account
holding MPWR Common Stock 49.5K 19 Nov 2025 Sciammas Family Trust
holding MPWR Common Stock 26.7K 19 Nov 2025 Various Sciammas GRATs
holding MPWR Common Stock 1.7K 19 Nov 2025 The Patrick Francis Sciammas 2020 Irrevocable Trust
holding MPWR Common Stock 4.02K 19 Nov 2025 By Sciammas Trust 2020
holding MPWR Common Stock 5K 19 Nov 2025 Clement Sciammas Family 2021 Trust
holding MPWR Common Stock 1K 19 Nov 2025 Peter Rafferty and Eric Toothill 2021Trust
holding MPWR Common Stock 1.7K 19 Nov 2025 The Chloe Liliane Sciammas 2020 Irrevocable Trust
holding MPWR Common Stock 1.5K 19 Nov 2025 Clement Sciammas Trust
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 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 $862.25 to $862.75. 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.
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 $866.16 to $866.51. 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 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 $867.04 to $867.98. 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.
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 $868.00 to $868.94. 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.
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 $869.00 to $869.91. 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.
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 $870.07 to $870.98. 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.
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 $871.39 to $871.64. 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.
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 $872.74 to $872.89. 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.
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 $873.49 to $873.97. 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.
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 $874.09 to $874.90. 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.