Monolithic Power (MPWR) insider files Form 144 to sell 400 shares

Rhea-AI Filing Summary

Monolithic Power Systems (MPWR) Form 144 shows a planned sale of 400 common shares through Morgan Stanley Smith Barney LLC on NASDAQ, with an aggregate market value of $340,000. The filing reports 47,892,000 shares outstanding, so the 400-share sale represents roughly 0.0008% of the companys outstanding stock.

The securities to be sold were acquired as restricted stock on 02/07/2024 (270 shares) and 02/08/2023 (130 shares). The notice also lists a prior sale by JEFF ZHOU of 200 shares on 08/12/2025 for gross proceeds of $166,000. The document includes the standard representation that the seller is not aware of undisclosed material adverse information about the issuer.

Positive

• Transaction uses a major broker (Morgan Stanley Smith Barney LLC), indicating standard execution channels
• Sale size is tiny relative to total shares outstanding (~0.0008%), implying minimal market impact

Negative

• None.

Insights

Securities Analyst

TL;DR: Small insider sale planned; transaction size is negligible relative to market capitalization.

The filing indicates a proposed sale of 400 common shares (aggregate value $340,000) via a major broker on NASDAQ. Given 47.892 million shares outstanding, the stake is immaterial (~0.0008%), so market impact is expected to be minimal. The shares were issued as restricted stock in 2023 and 2024, suggesting this is a routine disposal of vested awards rather than an event tied to operational changes. Recent sale of 200 shares for $166,000 provides a recent execution reference.

Corporate Governance Expert

TL;DR: Insider disposals are disclosed appropriately; no governance red flags apparent from this notice alone.

The filing follows Rule 144 disclosure norms, naming the broker and listing acquisition details for the shares being sold. The presence of restricted-stock acquisitions and a recent small sale by JEFF ZHOU are consistent with normal insider liquidity events. There is no indication in the filing of undisclosed material information or unusual transaction structure; therefore, the governance implication is neutral based on available data.

Form 144 Filer Information	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 144 NOTICE OF PROPOSED SALE OF SECURITIES PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
FORM 144

144: Filer Information

Filer CIK
Filer CCC
Is this a LIVE or TEST Filing?	LIVE TEST
Submission Contact Information
Name
Phone
E-Mail Address

144: Issuer Information

Name of Issuer

SEC File Number

Address of Issuer

Phone

Name of Person for Whose Account the Securities are To Be Sold

See the definition of "person" in paragraph (a) of Rule 144. Information is to be given not only as to the person for whose account the securities are to be sold but also as to all other persons included in that definition. In addition, information shall be given as to sales by all persons whose sales are required by paragraph (e) of Rule 144 to be aggregated with sales for the account of the person filing this notice.

Relationship to Issuer

144: Securities Information

Title of the Class of Securities To Be Sold	Name and Address of the Broker	Number of Shares or Other Units To Be Sold	Aggregate Market Value	Number of Shares or Other Units Outstanding	Approximate Date of Sale	Name the Securities Exchange
Common	Morgan Stanley Smith Barney LLC Executive Financial Services 1 New York Plaza 8th Floor New York NY 10004	400	340000.00	47892000	08/13/2025	NASDAQ

Furnish the following information with respect to the acquisition of the securities to be sold and with respect to the payment of all or any part of the purchase price or other consideration therefor:

144: Securities To Be Sold

Title of the Class	Date you Acquired	Nature of Acquisition Transaction	Name of Person from Whom Acquired	Is this a Gift?	Date Donor Acquired	Amount of Securities Acquired	Date of Payment	Nature of Payment *
Common	02/07/2024	Restricted Stock	ISSUER			270	02/07/2024	Not Applicable
Common	02/08/2023	Restricted Stock	ISSUER			130	02/08/2023	Not Applicable

* If the securities were purchased and full payment therefor was not made in cash at the time of purchase, explain in the table or in a note thereto the nature of the consideration given. If the consideration consisted of any note or other obligation, or if payment was made in installments describe the arrangement and state when the note or other obligation was discharged in full or the last installment paid.

Furnish the following information as to all securities of the issuer sold during the past 3 months by the person for whose account the securities are to be sold.

144: Securities Sold During The Past 3 Months

Name and Address of Seller	Title of Securities Sold	Date of Sale	Amount of Securities Sold	Gross Proceeds
JEFF ZHOU 5808 Lake Washington Blvd. NE Kirkland WA 98033	Common	08/12/2025	200	166000.00

144: Remarks and Signature

Remarks

Date of Notice

ATTENTION:

The person for whose account the securities to which this notice relates are to be sold hereby represents by signing this notice that he does not know any material adverse information in regard to the current and prospective operations of the Issuer of the securities to be sold which has not been publicly disclosed. If such person has adopted a written trading plan or given trading instructions to satisfy Rule 10b5-1 under the Exchange Act, by signing the form and indicating the date that the plan was adopted or the instruction given, that person makes such representation as of the plan adoption or instruction date.

Signature

ATTENTION: Intentional misstatements or omission of facts constitute Federal Criminal Violations (See 18 U.S.C. 1001)

FAQ

What is being sold in the MPWR Form 144?

400 common shares of Monolithic Power Systems, with an aggregate market value of $340,000, to be sold on NASDAQ.

Who executed recent sales listed in this filing?

JEFF ZHOU is listed as having sold 200 shares on 08/12/2025 for gross proceeds of $166,000.

How were the shares being sold originally acquired?

The 400 shares were acquired as restricted stock: 270 shares on 02/07/2024 and 130 shares on 02/08/2023.

Which broker will handle the sale?

Morgan Stanley Smith Barney LLC (Executive Financial Services, 1 New York Plaza, 8th Floor, New York, NY).

What percentage of outstanding shares does this sale represent?

The planned sale of 400 shares represents about 0.0008% of the 47,892,000 shares outstanding reported in the filing.