BlackRock (NYSE: BLK) discloses 10.2% stake in Monolithic Power Systems

Rhea-AI Filing Summary

BlackRock, Inc. has filed an amended Schedule 13G reporting beneficial ownership of 4,899,383 shares of Monolithic Power Systems, Inc. common stock, representing 10.2% of the class as of 12/31/2025. BlackRock reports sole voting power over 4,567,525 shares and sole dispositive power over all 4,899,383 shares, with no shared voting or dispositive power.

BlackRock states that the shares are held by certain of its business units in the ordinary course of business and not for the purpose of changing or influencing control of Monolithic Power Systems. Various underlying clients have rights to dividends or sale proceeds, but no single client holds more than five percent of the outstanding common shares.

Insights

Institutional ownership analyst

BlackRock discloses a passive 10.2% stake in Monolithic Power Systems.

BlackRock, Inc. reports beneficial ownership of 4,899,383 shares of Monolithic Power Systems common stock, equal to 10.2% of the class as of 12/31/2025. It reports sole voting power over 4,567,525 shares and sole dispositive power over the full 4,899,383 shares, with no shared authority.

The position is reported on a Schedule 13G, which is used for holdings certified as passive. BlackRock confirms the shares were acquired and are held in the ordinary course of business and not with the purpose or effect of changing or influencing control, indicating a typical institutional investment position.

The disclosure also notes that various underlying clients have rights to dividends or sale proceeds, but no single client has an interest exceeding five percent of Monolithic Power Systems’ outstanding common shares. Future ownership levels will depend on portfolio management decisions within BlackRock’s reporting business units.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 4)

MONOLITHIC POWER SYSTEMS INC

(Name of Issuer)

Common Stock

(Title of Class of Securities)

609839105

(CUSIP Number)

12/31/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 609839105

1

Names of Reporting Persons

BlackRock, Inc.

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 4,567,525.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 4,899,383.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

4,899,383.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

10.2 %

12

Type of Reporting Person (See Instructions)

HC

SCHEDULE 13G

Item 1.
(a)	Name of issuer: MONOLITHIC POWER SYSTEMS INC
(b)	Address of issuer's principal executive offices: 5808 LAKE WASHINGTON BLVD. NE KIRKLAND WA 98033
Item 2.
(a)	Name of person filing: BlackRock, Inc. In accordance with SEC Release No. 34-39538 (January 12, 1998), this Schedule 13G reflects the securities beneficially owned, or deemed to be beneficially owned, by certain business units (collectively, the "Reporting Business Units") of BlackRock, Inc. and its subsidiaries and affiliates. It does not include securities, if any, beneficially owned by other business units whose beneficial ownership of securities are disaggregated from that of the Reporting Business Units in accordance with such release.
(b)	Address or principal business office or, if none, residence: BlackRock, Inc., 50 Hudson Yards New York, NY 10001
(c)	Citizenship: See Item 4 of Cover Page
(d)	Title of class of securities: Common Stock
(e)	CUSIP No.: 609839105
Item 4.	Ownership
(a)	Amount beneficially owned: 4899383
(b)	Percent of class: 10.2 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 4567525
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 4899383
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	Ownership of 5 Percent or Less of a Class.
	Not Applicable
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required. Various persons have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of the common stock of MONOLITHIC POWER SYSTEMS INC. No one person's interest in the common stock of MONOLITHIC POWER SYSTEMS INC is more than five percent of the total outstanding common shares.
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary. See Exhibit 99
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

BlackRock, Inc.

Signature:	Spencer Fleming
Name/Title:	Managing Director
Date:	01/08/2026

Exhibit Information

Exhibit 24: Power of Attorney Exhibit 99: Item 7

FAQ

How many Monolithic Power Systems shares does BlackRock (BLK) report owning?

BlackRock reports beneficial ownership of 4,899,383 shares of Monolithic Power Systems common stock as of 12/31/2025.

What percentage of Monolithic Power Systems’ common stock does BlackRock (BLK) hold?

BlackRock reports that its 4,899,383 shares represent 10.2% of Monolithic Power Systems’ outstanding common stock.

Does BlackRock have voting control over its Monolithic Power Systems shares?

BlackRock reports sole voting power over 4,567,525 shares and no shared voting power in Monolithic Power Systems.

Is BlackRock’s stake in Monolithic Power Systems reported as passive or active?

BlackRock certifies the position as held in the ordinary course of business and not for changing or influencing control, consistent with a passive Schedule 13G filing.

Who ultimately benefits from BlackRock’s Monolithic Power Systems holdings?

The Schedule 13G states that various persons have rights to dividends or sale proceeds from the Monolithic Power Systems shares, and no one person’s interest exceeds 5% of the total outstanding common shares.

Which BlackRock units are included in this Monolithic Power Systems ownership report?

The statement reflects securities beneficially owned, or deemed to be beneficially owned, by certain Reporting Business Units of BlackRock, Inc. and its subsidiaries and affiliates, excluding other disaggregated business units.