Mr. Eugen J. Elmiger - 06 May 2026 Form 4 Insider Report for MONOLITHIC POWER SYSTEMS INC (MPWR)

Reporting relationship: Director
Issuer ticker: MPWR
Reported as of: 06 May 2026
Net transaction value: -$19,019,482
SEC form: 4
Accepted by SEC: 08 May 2026, 19:37:38 UTC
Prior SEC filing: 05 Feb 2026
Source filing: View source filing
Reporting owner signature: /s/ Saria Tseng, attorney-in-fact for Mr. Eugen J. Elmiger

Key filing fact

Mr. Eugen J. Elmiger filed Form 4 for MONOLITHIC POWER SYSTEMS INC (MPWR) on 08 May 2026.

Key facts

This page summarizes Mr. Eugen J. Elmiger's Form 4 filing for MONOLITHIC POWER SYSTEMS INC (MPWR).
9 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 08 May 2026, 19:37.

Change

Previous filing in this sequence was filed on 05 Feb 2026.
Current net transaction value: -$19,019,482.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001560945 Primary reporting owner

Elmiger Eugen J

Relationship: Director
Address: 1555 PALM BEACH LAKES BLVD., WEST PALM BEACH
Signature: /s/ Saria Tseng, attorney-in-fact for Mr. Eugen J. Elmiger
Signature date: 08 May 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

MPWR transaction

Common Stock

Sale

Transaction value: $499,162
Shares: -320
Change %: -1.8%
Price: $1559.88
Shares after: 17,082
Date: 06 May 2026
Ownership: Direct
Footnotes: F1

MPWR transaction

Common Stock

Sale

Transaction value: $1,275,017
Shares: -814
Change %: -4.8%
Price: $1566.36
Shares after: 16,268
Date: 06 May 2026
Ownership: Direct
Footnotes: F2

MPWR transaction

Common Stock

Sale

Transaction value: $1,694,163
Shares: -1,078
Change %: -6.6%
Price: $1571.58
Shares after: 15,190
Date: 06 May 2026
Ownership: Direct
Footnotes: F3

MPWR transaction

Common Stock

Sale

Transaction value: $1,314,025
Shares: -834
Change %: -5.5%
Price: $1575.57
Shares after: 14,356
Date: 06 May 2026
Ownership: Direct
Footnotes: F4

MPWR transaction

Common Stock

Sale

Transaction value: $2,972,221
Shares: -1,879
Change %: -13%
Price: $1581.81
Shares after: 12,477
Date: 06 May 2026
Ownership: Direct
Footnotes: F5

MPWR transaction

Common Stock

Sale

Transaction value: $4,105,077
Shares: -2,587
Change %: -21%
Price: $1586.81
Shares after: 9,890
Date: 06 May 2026
Ownership: Direct
Footnotes: F6

MPWR transaction

Common Stock

Sale

Transaction value: $2,156,320
Shares: -1,355
Change %: -14%
Price: $1591.38
Shares after: 8,535
Date: 06 May 2026
Ownership: Direct
Footnotes: F7

MPWR transaction

Common Stock

Sale

Transaction value: $4,181,024
Shares: -2,619
Change %: -31%
Price: $1596.42
Shares after: 5,916
Date: 06 May 2026
Ownership: Direct
Footnotes: F8

MPWR transaction

Common Stock

Sale

Transaction value: $822,472
Shares: -514
Change %: -8.7%
Price: $1600.14
Shares after: 5,402
Date: 06 May 2026
Ownership: Direct
Footnotes: F9

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 9 footnotes

Footnote 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 $1,557.08 to $1,561.97. 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.

Footnote 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 $1,563.39 to $1,568.28. 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.

Footnote 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 $1,568.78 to $1,573.40. 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.

Footnote 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 $1,573.86 to $1,578.73. 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.

Footnote 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 $1,578.85 to $1,583.66. 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.

Footnote 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 $1,583.79 to $1,588.65. 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.

Footnote 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 $1,588.80 to $1,593.63. 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.

Footnote 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 $1,593.95 to $1,598.78. 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.

Footnote 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 $1,598.99 to $1,602.68 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.