Welcome to our dedicated page for Monolithic Power 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, Inc. updated its corporate bylaws to make it easier for investors to call a special shareholder meeting. On November 19, 2025, the Board approved Amended and Restated Bylaws that lower the ownership threshold required to request a special meeting from at least 30% to at least 25% of the company’s outstanding voting capital stock.
The Board explains that it considered the 2025 annual meeting, where stockholders approved a non-binding proposal to set the threshold at 10%, along with feedback from a majority in interest of its top ten stockholders, who preferred a significantly higher threshold than 10%, and a review of peer practices. The full amended bylaws are filed as an exhibit and are effective immediately.
Monolithic Power Systems (MPWR) reported insider activity by its EVP, WW Sales & Marketing, in a Form 4 filing. On 11/19/2025, the executive sold multiple blocks of common stock in open market transactions coded "S" for sales.
The reported trades covered relatively small share blocks at weighted average prices ranging from about $875.26 to $886.01, with detailed price ranges provided for each group of sales. After these transactions, the reporting person directly held 148,306 shares of MPWR common stock.
The filing also lists additional indirect beneficial ownership in various family trusts and related accounts, each holding smaller amounts of MPWR shares. The trades were reported as having been made under a Rule 10b5-1 trading arrangement, which is a pre-established plan for buying or selling stock.
Monolithic Power Systems (MPWR) executive vice president of worldwide sales and marketing Maurice Sciammas reported multiple open-market sales of common stock on 11/19/2025. Across a series of trades, he sold a total of 7,034 shares at weighted average prices reported between about $862 and $875 per share, with detailed price ranges noted for each trade.
After these transactions, Sciammas directly owned 176,272 shares of MPWR common stock and also had additional indirect holdings through various family trusts and accounts, including positions such as 49,460 shares in the Sciammas Family Trust and other named family and irrevocable trusts. The footnotes state that the reported prices are weighted averages and that full trade-by-trade price information is available upon request.
Monolithic Power Systems (MPWR) reported insider transactions by CEO and director Michael R. Hsing. On 11/12/2025, he executed multiple open‑market sales of common stock at disclosed weighted‑average prices, with per‑line price ranges provided.
Following the transactions, Hsing beneficially owns 918,669 shares directly. He also holds indirect positions of 133,040 shares via the M Hsing 04 Trust and 12,825 shares via the ZH Family 2020 Trust.
Monolithic Power Systems (MPWR) CEO and director Michael R. Hsing reported open-market sales of 40,000 shares of common stock on 11/11/2025 across multiple transactions. The filing lists weighted-average prices for each tranche, with disclosed price ranges from $952.05 to $967.17 for the respective trades. Following these sales, Hsing directly holds 955,669 shares.
The filing also shows indirect holdings of 133,040 shares by the M Hsing 04 Trust and 12,825 shares by the ZH Family 2020 Trust.
Monolithic Power Systems (MPWR) reported an insider transaction by its EVP, WW Sales & Marketing. On 11/05/2025, the reporting person sold 200 shares of common stock at $986.81 per share.
Following the transaction, the report lists beneficial ownership positions, including 183,306 shares direct and 44,930 shares held indirectly in the Sciammas Family Trust, among various other family trusts and accounts.
Monolithic Power Systems (MPWR) reported strong Q3 2025 results. Revenue reached $737.2 million, up 18.9% year over year, with gross margin at 55.1%. Operating income was $195.2 million and net income was $178.3 million, delivering diluted EPS of $3.71 versus $2.95 a year ago.
Year to date, revenue rose to $2.04 billion (up 28.6%), and net income increased to $445.8 million. Growth was broad-based: storage and computing, automotive, and industrial led gains, while enterprise data was mixed over nine months. Asia remained the largest region, with China at $393.8 million in Q3.
MPWR ended the quarter with $1.08 billion in cash and cash equivalents and generated $733.3 million in operating cash flow for the first nine months. The company returned capital via dividends of $1.56 per share in Q3 (total $4.68 year to date) and modest buybacks, while increasing inventories and investing in capacity and operations.
Monolithic Power Systems (MPWR) executive Bernie Blegen, EVP and CFO, reported open-market sales of common stock on 11/03/2025 pursuant to a Rule 10b5-1 trading plan adopted on 2/26/2025.
The sales were executed in multiple small lots at weighted average prices, including $1,013.62, $1,019.49, and $1,038.41 per share. Following these transactions, Blegen beneficially owns 74,332 shares directly.
He also reports indirect holdings of 5,331 shares in the Irrevocable Trust FBO Sarah N. Blegen and 5,331 shares in the Irrevocable Trust FBO Theodore F. Blegen.
Monolithic Power Systems (MPWR) — Form 4 insider filing: CEO and Director Michael R. Hsing reported a Code F transaction on 10/30/2025. The filing shows 121,918 shares of common stock were withheld by the company at $1,096.63 per share to satisfy income tax obligations tied to the earnout and vesting of market-based RSUs granted in October 2022.
After the withholding, Hsing beneficially owns 995,669 shares directly. He also has indirect holdings of 133,040 shares through the M Hsing 04 Trust and 12,825 shares through the ZH Family 2020 Trust. Code F indicates a tax-withholding event rather than an open-market sale.
Monolithic Power Systems (MPWR) EVP and CFO Bernie Blegen reported a Form 4 transaction. On 10/30/2025, 48,298 shares of common stock were withheld at $1,096.63 per share to satisfy income taxes related to the earnout and vesting of market-based RSUs granted in October 2022.
Following the transaction, Blegen directly owned 77,332 shares. Indirect holdings include 5,331 shares in an irrevocable trust for Sarah N. Blegen and 5,331 shares in an irrevocable trust for Theodore F. Blegen.