MPWR (NASDAQ) Form 144: Insider S. Tseng sold 48,550 shares across Feb–Mar 2026

Rhea-AI Filing Summary

Morgan Stanley Smith Barney LLC submitted a Form 144 notice relating to Common stock described as Performance Shares. The filing lists 1400 in the securities row and records recent sales by Saria Tseng: 22,876 shares on 02/06/2026 and 25,674 shares on 03/30/2026.

Key Figures

Recent sale by Saria Tseng: 25,674 shares Recent sale by Saria Tseng: 22,876 shares Row quantity listed: 1,400

3 metrics

Recent sale by Saria Tseng 25,674 shares sale date 03/30/2026

Recent sale by Saria Tseng 22,876 shares sale date 02/06/2026

Row quantity listed 1,400 appears in securities rows alongside Common/Performance Shares

Key Terms

Form 144, Performance Shares, Issuer

3 terms

Form 144 regulatory

"Filer Information | | | 144: Filer Information"

Form 144 is a document that investors must file with the government when they plan to sell a large number of shares of a company's stock. It helps ensure transparency so everyone knows how many shares are being sold and when, which can impact the stock's price.

Performance Shares financial

"Common | 01/01/2024 | Performance Shares | ISSUER"

Performance shares are a type of company stock given to executives or employees that only become theirs if the company meets specific goals, like hitting certain profits or growth targets. They motivate leaders to work toward the company’s success, because their additional shares depend on achieving these results.

Issuer financial

"Performance Shares | ISSUER | | | 1400"

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	1586924.78	49118000	04/01/2026	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			1400	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

Name and Address of Seller	Title of Securities Sold	Date of Sale	Amount of Securities Sold	Gross Proceeds
SARIA TSENG 1555 Palm Beach Lakes Blvd. West Palm Beach FL 33401	Common	03/30/2026	25674	25943648.15
SARIA TSENG 1555 Palm Beach Lakes Blvd. West Palm Beach FL 33401	Common	02/06/2026	22876	26791540.80

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)

FAQ

What does MPWR's Form 144 report?

The Form 144 reports a proposed sale of common stock described as Performance Shares. It also lists recent sales by Saria Tseng: 22,876 shares on 02/06/2026 and 25,674 shares on 03/30/2026.

Who is listed as the filer on the MPWR Form 144?

The filer is listed as Morgan Stanley Smith Barney LLC with an address at 1 New York Plaza, 8th Floor, New York, NY. The filing identifies the securities as Common (Performance Shares).

How many shares did Saria Tseng sell recently according to the filing?

The filing shows two sales by Saria Tseng: 22,876 shares on 02/06/2026 and 25,674 shares on 03/30/2026. The filing lists these amounts without additional context.

Does the Form 144 state where the shares will trade?

Yes. The filing lists NASDAQ as the market identifier for the securities row where Common stock is shown. No execution details or brokers beyond the filer are provided in the excerpt.

Is the number 1400 meaningful in this Form 144?

The number 1400 appears in the securities rows in the excerpt alongside the common stock entry. The filing text presents it directly but does not add explanatory labels within the provided excerpt.