Form 4: MPWR EVP Sells $24.6M in Pre-Planned Stock Sale

Monolithic Power Systems' EVP of Worldwide Sales & Marketing, Maurice Sciammas, sold 27,966 shares of common stock for approximately $24.6 million on November 19, 2025, under a Rule 10b5-1 plan.

Summary

• Maurice Sciammas, EVP, WW Sales & Marketing at Monolithic Power Systems Inc. (MPWR), reported direct sales of common stock.
• A total of 27,966 shares were sold on November 19, 2025, as part of a pre-arranged Rule 10b5-1 plan.
• The sales occurred across multiple transactions with weighted average prices ranging from $875.26 to $886.01 per share, with individual transaction prices ranging from $875.01 to $886.15.
• The estimated total value of shares sold is approximately $24.6 million.
• Following these transactions, Sciammas directly beneficially owns 148,306 shares of common stock.
• Sciammas also indirectly beneficially owns 96,030 shares through various family trusts and accounts.

Sentiment

Score: 5

Explanation: The sale of shares by a key executive, while significant, was executed under a pre-arranged Rule 10b5-1 plan. This indicates the transaction was scheduled in advance and not based on immediate, non-public information, which mitigates the negative sentiment typically associated with insider selling.

Negatives

• A significant divestment of 27,966 shares by a key executive, even if pre-planned, can sometimes be viewed with caution by investors.

Risks

• While executed under a 10b5-1 plan, large insider sales can still lead to negative investor sentiment or speculation, potentially causing short-term selling pressure on the stock.

Future Outlook

The filing does not contain any forward-looking statements or guidance regarding the company's future performance.

Industry Context

Insider transactions, particularly by high-ranking executives, are closely watched in the semiconductor and power management industry as they can offer insights into management's perspective on the company's valuation. However, sales made under a Rule 10b5-1 plan are generally considered less indicative of immediate company prospects as they are pre-scheduled.

Related Party Transactions

• Maurice Sciammas indirectly holds shares through various family trusts and accounts, including The Joseph Roger Sciammas 2020 Irrevocable Trust (1,699 shares), Rosalind Sciammas Family 2021 Trust (2,000 shares), Rosalind Sciammas Brokerage Account (1,299 shares), Sciammas Family Trust (49,460 shares), Various Sciammas GRATs (26,660 shares), The Patrick Francis Sciammas 2020 Irrevocable Trust (1,699 shares), By Sciammas Trust 2020 (4,015 shares), Clement Sciammas Family 2021 Trust (5,000 shares), Peter Rafferty and Eric Toothill 2021Trust (1,000 shares), The Chloe Liliane Sciammas 2020 Irrevocable Trust (1,699 shares), and Clement Sciammas Trust (1,499 shares).

Stakeholder Impact

• Shareholders may scrutinize the executive's sale, but the 10b5-1 plan context suggests it's for personal financial management rather than a reflection of company performance, thus limiting potential negative impact on sentiment.

Key Dates

Recommendation

The executive's sale of shares, while substantial, was conducted under a Rule 10b5-1 plan. This pre-scheduled nature suggests the transaction is for personal financial management rather than a reaction to new, adverse company developments. Therefore, it does not necessarily signal a change in the company's fundamental outlook. Investors should maintain a 'hold' position, continuing to monitor company performance and broader market trends rather than reacting solely to this pre-planned insider transaction.

Keywords

Monolithic Power Systems, MPWR, Insider Trading, Form 4, Stock Sale, Executive Compensation, Rule 10b5-1, Semiconductor, Power Management, Maurice Sciammas