Monolithic Power Systems (MPWR) director sells 335 shares

Rhea-AI Filing Summary

Monolithic Power Systems director Eileen Wynne sold shares in an open-market trade. On May 6, 2026, she sold 335 shares of Common Stock at an average price of $1,582.68 per share. After this sale, she directly held 1,007 shares of Monolithic Power Systems stock.

Insider Trade Summary

Net Seller: 335 shares ($530,198)

Net Sell 1 txn

Insider Wynne Eileen

Role null

Sold 335 shs ($530K)

Type	Security	Shares	Price	Value
Sale	Common Stock	335	$1,582.68	$530K

Holdings After Transaction: Common Stock — 1,007 shares (Direct, null)

Footnotes (1)

Key Figures

Shares sold: 335 shares Average sale price: $1,582.68 per share Shares held after transaction: 1,007 shares

3 metrics

Shares sold 335 shares Open-market sale on May 6, 2026

Average sale price $1,582.68 per share Common Stock open-market transaction

Shares held after transaction 1,007 shares Direct ownership following May 6, 2026 sale

Key Terms

open-market sale, Common Stock, Form 4

3 terms

open-market sale financial

"transaction_action: "open-market sale""

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

Common Stock financial

"security_title: "Common Stock""

Common stock represents ownership shares in a company, giving investors a stake in its success and a say in important decisions through voting rights. It is the most common type of stock traded on markets and can provide income through dividends, as well as potential for value growth. For investors, holding common stock means sharing in the company’s profits and risks.

Form 4 regulatory

"INSIDER FILING DATA (Form 4)"

Form 4 is a official document that company insiders, such as executives or major shareholders, file with regulators whenever they buy or sell company shares. It provides transparency about how those with inside knowledge are trading, helping investors see if insiders are confident in the company's prospects or may be selling for personal reasons. This information can influence investor decisions by revealing insiders' perspectives on the company's value.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a 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). See Instruction 10.

1. Name and Address of Reporting Person^*

Wynne Eileen

(Last) (First) (Middle)

1555 PALM BEACH LAKES BLVD.

(Street)

WEST PALM BEACH FLORIDA 33401

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
MONOLITHIC POWER SYSTEMS INC [ MPWR ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/06/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	05/06/2026		S		335	D	$1,582.68	1,007	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

Remarks:

	/s/ Saria Tseng, attorney-in-fact for Ms. Eileen Wynne	05/08/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did MPWR director Eileen Wynne report?

Director Eileen Wynne reported an open-market sale of 335 MPWR Common Stock shares. The transaction occurred on May 6, 2026, at an average price of $1,582.68 per share, and left her with 1,007 shares owned directly after the sale.

How many MPWR shares did Eileen Wynne sell and at what price?

Eileen Wynne sold 335 MPWR Common Stock shares in an open-market transaction. The reported average sale price was $1,582.68 per share on May 6, 2026, according to the Form 4 insider filing data for Monolithic Power Systems.

How many MPWR shares does Eileen Wynne hold after this Form 4 sale?

Following the reported sale, Eileen Wynne directly holds 1,007 MPWR Common Stock shares. This figure comes from the Form 4, which shows her position immediately after selling 335 shares on May 6, 2026, in an open-market transaction.

Was the MPWR insider trade by Eileen Wynne a buy or a sell?

The MPWR insider trade reported by director Eileen Wynne was a sale. The Form 4 classifies it as an open-market sale of 335 Common Stock shares at $1,582.68 per share, leaving her with 1,007 shares held directly afterward.

What type of security did MPWR director Eileen Wynne trade?

Eileen Wynne traded Monolithic Power Systems Common Stock, rather than options or other derivatives. The Form 4 lists a non-derivative transaction: an open-market sale of 335 Common Stock shares at an average price of $1,582.68 per share.