Monolithic Power Systems insider files Rule 144 to sell 20,231 shares

Rhea-AI Filing Summary

Form 144 notice from an insider of Monolithic Power Systems, Inc. (MPWR) reports a proposed sale of common stock. The filing names Morgan Stanley Smith Barney LLC as broker and lists 20,231 shares planned for sale on 08/15/2025 on the NASDAQ with an aggregate market value of $16,773,556.49. The shares were acquired as performance shares from the issuer on 01/01/2024. The filer reports 47,892,000 shares outstanding for the class and indicates no securities sold by the filer in the past three months. The notice includes the standard certification that the seller is not aware of undisclosed material adverse information and references Rule 10b5-1 plan language but does not state a plan adoption date.

Positive

• Regulatory compliance: The insider filed a Rule 144 notice and identified the broker and sale details.
• No recent sales: The filer reports nothing to report for securities sold in the past three months.

Negative

• Unclear trading plan: The filing does not state a Rule 10b5-1 plan adoption date, leaving the timing rationale unspecified.
• Single large-block sale: The notice indicates an aggregate market value of $16,773,556.49, which may be material to market perception despite being a routine disclosure.

Insights

Financial Analyst

TL;DR: An insider plans a single-block sale of performance shares through Morgan Stanley; transaction is disclosed but not clearly tied to a trading plan.

The filing shows a 20,231-share disposal with an aggregate market value stated as $16.77 million, executed via a major broker on NASDAQ. Shares were granted as performance-based compensation on 01/01/2024. Absence of reported sales in the prior three months reduces the likelihood of ongoing selling pressure from this account, but the document does not specify a 10b5-1 plan adoption date. For investors, this is a routine insider liquidity event disclosed under Rule 144 rather than a company operational update.

Corporate Governance Expert

TL;DR: Proper Rule 144 disclosure filed; governance implications hinge on whether sale follows a pre-established trading plan.

The form identifies the nature of acquisition as performance shares and includes the required seller certification about material nonpublic information. The filing does not state a 10b5-1 plan date, which matters for interpreting whether the sale is scheduled or discretionary. The disclosure meets regulatory form requirements and signals standard insider monetization of compensation awards rather than an immediate governance concern.

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

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	20231	16773556.49	47892000	08/15/2025	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	01/01/2024	Performance Shares	Issuer			20231	01/01/2024	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

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 does the MPWR Form 144 disclose about the planned sale?

The filing discloses a planned sale of 20,231 common shares via Morgan Stanley on NASDAQ on 08/15/2025 with an aggregate market value of $16,773,556.49.

When and how were the shares being sold acquired?

The shares were acquired as performance shares from the issuer on 01/01/2024 and payment is listed as Not Applicable.

Has the filer sold any MPWR securities in the past three months?

The filing states Nothing to Report for securities sold during the past three months by the person for whose account the securities are to be sold.

Does the Form 144 state the filer adopted a 10b5-1 trading plan?

No. The form includes the standard statement about 10b5-1 plans but does not provide a plan adoption date or indicate that a plan governs this sale.

Who is the broker handling the sale listed on the filing?

The listed broker is Morgan Stanley Smith Barney LLC Executive Financial Services, 1 New York Plaza, 8th Floor, New York, NY 10004.