Welcome to our dedicated page for MONOLITHIC POWER SYSTEMS SEC filings (Ticker: MPWR), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Monolithic Power Systems filings document regulatory disclosures for a fabless semiconductor company focused on power electronics solutions. Its 8-K filings furnish quarterly and annual operating results, earnings commentary, cash dividend declarations, officer-transition disclosures, and other material events tied to financial reporting.
The filing record also includes proxy materials covering annual meeting matters, director and executive compensation disclosures, and stockholder voting procedures. Other filings describe governance amendments such as bylaw changes affecting special-meeting rights, and reporting-controls matters including non-reliance determinations and restatement-related disclosures for previously issued financial statements.
Monolithic Power Systems (MPWR) executive Deming Xiao, EVP, Global Operations, reported the acquisition of 135,520 shares of common stock on October 25, 2025 at $0 per share. The shares were awarded upon certification of performance for market-based restricted stock units (MSUs) granted on October 25, 2022, tied to five stock price targets and relative total stockholder return over a three-year period; all shares vested on October 25, 2025.
Following the transaction, the filing shows 256,180 shares beneficially owned directly, plus 20,455 shares indirectly by spouse and 4,336 shares indirectly by the Christopher Chao Xiao Trust.
Monolithic Power Systems (MPWR) reported an insider transaction for EVP, WW Sales & Marketing, Maurice Sciammas. On October 25, 2025, the Compensation Committee certified the performance of previously granted market-based RSUs, resulting in an award of 135,520 shares. All awarded shares fully vested on the same date at a reported price of $0.
Following the transaction, Sciammas beneficially owns 237,849 shares directly. The ending balance includes 4 shares acquired on August 15, 2025 through the company’s ESPP. The filing also lists multiple indirect holdings across family trusts and accounts.
Monolithic Power Systems (MPWR) reported an insider transaction by its EVP & General Counsel. On 10/24/2025, the reporting person sold 1,300 shares of common stock at a price of $1,087.62 per share under transaction code “S.” Following the sale, the filer beneficially owned 126,354 shares, held directly. The filing notes the trade was made pursuant to a Rule 10b5-1 trading plan adopted on 8/30/2024.
Monolithic Power Systems (MPWR) executive Saria Tseng, EVP & General Counsel, reported open-market sales of common stock under a Rule 10b5-1 plan. On 10/15/2025, she sold 14,028 shares at $1,016.18. On 10/16/2025, she sold 1,499 shares at $1,021.26 and 1,313 shares at $1,030.81. Following these transactions, her beneficial ownership decreased to 127,654 shares. The trading plan was adopted on 8/30/2024.
Monolithic Power Systems (MPWR) Form 4 reports multiple open-market sales by EVP and CFO Theodore Blegen executed on 10/01/2025 under a Rule 10b5-1 trading plan adopted 02/26/2025. The schedule shows a sequence of sales at weighted-average prices ranging from $902.61 to $917.17 per share across separate blocks, reducing Mr. Blegen's direct holdings from earlier reported balances down to 37,940 shares held directly. The filing also discloses indirect ownership of 5,331 shares in an irrevocable trust for Theodore F. Blegen and 5,331 shares in an irrevocable trust for Sarah N. Blegen. The form is signed by an attorney-in-fact.
Form 144 filing for MPWR (Monolithic Power Systems Inc.): The notice reports a proposed sale of 3,000 common shares to be executed through Morgan Stanley Smith Barney LLC on 10/01/2025 on NASDAQ, with an aggregate market value of $2,739,643.80. The shares were acquired as performance shares from the issuer on 07/20/2023 and paid for on that date. The filing lists 47,892,000 shares outstanding for the class. The filer, identified in sale history as Bernie Blegen, sold 3,000, 3,000, and 6,000 common shares on 09/02/2025, 08/01/2025, and 07/01/2025 respectively, generating gross proceeds of $2,443,025.70, $2,250,000.00, and $4,500,000.00.
Monolithic Power Systems (MPWR) director Carintia Martinez reported a sale of common stock under a 10b5-1 plan. On 09/18/2025 the reporting person sold 1,400 shares of Monolithic Power Systems common stock for a price reported as $900. After the sale the reporting person beneficially owned 878 shares. The filing states the transaction was executed pursuant to a Rule 10b5-1 trading plan adopted on 11/27/2024 and the Form 4 was signed by an attorney-in-fact on 09/18/2025.
Saria Tseng, EVP & General Counsel of Monolithic Power Systems, reported a sale of 14,510 shares of the company's common stock on 09/18/2025 at a price of $914.45 per share. The filing notes the sale was made pursuant to a Rule 10b5-1 trading plan adopted on 08/30/2024. After the reported transaction, the filing shows beneficial ownership of 144,494 shares, which includes 27 shares acquired through the company's qualified ESPP on 02/17/2025. The form is signed by the reporting person and discloses the relationship to the issuer as an officer.
Form 144 notice from Monolithic Power Systems, Inc. (MPWR) discloses a proposed sale of 14,510 common shares through Morgan Stanley Smith Barney LLC on 09/18/2025 on the NASDAQ with an aggregate market value of $13,268,669.50. The shares were acquired as performance shares from the issuer on 07/20/2023 and the filing reports no securities sold in the past three months by the selling person. The filer attests they are not aware of undisclosed material adverse information and the notice includes the standard signatures and Rule 10b5-1 plan disclosure fields.
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.