[144] MONOLITHIC POWER SYSTEMS INC SEC Filing

Rhea-AI Filing Summary

Monolithic Power Systems (MPWR) submitted a Form 144 notifying a proposed insider sale of common stock. The notice lists 1,400 shares to be sold through Morgan Stanley Smith Barney LLC on 09/18/2025, with an aggregate market value of $1,260,000 and 47,892,000 shares outstanding. The filing details the acquisition history for those shares as restricted stock received from the issuer on 02/08/2023 (542 shares), 05/27/2023 (291 shares), 05/27/2022 (292 shares), and 02/07/2024 (275 shares), with payment noted as not applicable. The filer reports nothing to report for securities sold in the past three months and includes the standard representation regarding material nonpublic information.

Insights

Securities/Equity Analyst

TL;DR: Insider filing reports a modest proposed sale of 1,400 shares valued at $1.26M, a routine disclosure.

The Form 144 notifies an intended sale executed through a broker on a specified date and discloses that the shares were received as restricted stock on multiple grant dates. The filing shows no related sales in the past three months, which suggests this is an isolated, pre-announced disposition rather than part of a larger recent pattern disclosed in this document. Information is purely a notice of proposed sale; it does not provide trading plan details beyond the broker, share count, value, or acquisition history.

Corporate Governance Expert

TL;DR: This Form 144 is a compliance disclosure of a planned sale; it contains standard representations and acquisition chronology.

The filing lists the broker, exact share count, aggregate market value, and acquisition dates for the restricted stock being sold. The signature attestation about material nonpublic information is included as required. The document does not disclose the seller's role, intent, or any trading-plan adoption date, so governance implications are limited to routine transparency obligations reflected in the filing itself.

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	1400	1260000.00	47892000	09/18/2025	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	02/08/2023	Restricted Stock	ISSUER			542	02/08/2023	Not Applicable
Common	05/27/2023	Restricted Stock	ISSUER			291	05/27/2023	Not Applicable
Common	05/27/2022	Restricted Stock	ISSUER			292	05/27/2022	Not Applicable
Common	02/07/2024	Restricted Stock	ISSUER			275	02/07/2024	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

Nothing to Report

144: Remarks and Signature

Remarks

Date of Notice

Date of Plan Adoption or Giving of Instruction, If Relying on Rule 10b5-1

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)