Company Atlasby KadoaStar on GitHub

Monolithic Power Systems MPWR

Monolithic Power Systems is the 215th largest S&P 500 company by market cap, worth $56.0 billion. 7 directors have filed with the SEC in the last 12 months (who counts), 1 of them an executive. 4 other officers are on file. At 30 Jun 2026, Vanguard was its largest institutional holder, with 12.5% of the company.

CEO
Michael Hsing
Sector
Information Technology
Sub-industry
Semiconductors
Headquarters
Kirkland, Washington
Founded
1997
More
Wikipedia
Market cap
$56.0B
215th largest, 23 Oct 2026 close
Revenue
$2.8B
Fiscal year 2025
Price to sales
20.1
Market cap over revenue
Employees
4,500
10-K, 31 Dec 2025
Market cap per employee
$12M
Market cap over employees
Connections
0
S&P 500 companies sharing a director or officer

Largest institutional holders

Each fund group's share of Monolithic Power Systems. Where a company has several share classes, the share is of its total value.

13F filings for the quarter to 30 Jun 2026

These five hold 43.9% of Monolithic Power Systems.

Source: SEC Form 13F data sets, SEC XBRL shares outstanding 路 All holders

Board and officers

Roles filed up to 30 Sep 2026

NameTitle
Directors (7)
Michael HsingCEOCEO
Kuo Wei Herbert ChangDirectorDirector
Eugen J. ElmigerDirectorDirector
Victor K. LeeDirectorLast filed 11 Feb 2026Director
Carintia MartinezDirectorLast filed 5 Feb 2026Director
Eileen WynneDirectorDirector
Jeff ZhouDirectorDirector
Officers (4)
Robert W. Dean IIInterim CFOLast filed 26 Aug 2026Interim CFO
Maurice SciammasEVP, WW Sales & MarketingLast filed 6 Aug 2026EVP, WW Sales & Marketing
Saria TsengEVP & General CounselLast filed 2 Sep 2026EVP & General Counsel
Deming XiaoEVP, Global OperationsLast filed 8 May 2026EVP, Global Operations

Source: SEC insider filings (Forms 3, 4 and 5), Monolithic Power Systems' Form 4 filings 路 All directors and officers

Monolithic Power Systems' market cap since December 2008

Weekly, up to 23 Oct 2026

Show equal percentage changes as equal steps.
201020122014201620182020202220242026$56.0B

Source: Yahoo Finance closing prices, SEC XBRL shares outstanding

Workforce

Headcount at 31 Dec 2025

Employees
4,500
We have over 4,500 employees worldwide, with various locations in Asia, Europe and the U.S.
Monolithic Power Systems Form 10-K

Source: Monolithic Power Systems Form 10-K

Insider trades

Open-market buys and sales by directors and officers. Grants, option exercises and shares withheld for tax are left out.

Trades from 30 Sep 2025 to 30 Sep 2026

Directors and officers sold $749 million of stock in 59 sales and made no open-market purchases in the 12 months to 30 Sep 2026.

DatePersonTitleTypeSharesValue
28 Sep 2026SaleMichael HsingCEOCEOSale30,000$40M
24 Aug 2026SaleKuo Wei Herbert ChangDirectorDirectorSale50$64K
24 Aug 2026SaleRobert W. Dean IIInterim CFOInterim CFOSale32$42K
17 Aug 2026SaleRobert W. Dean IIInterim CFOInterim CFOSale6$8K
11 Aug 2026SaleKuo Wei Herbert ChangDirectorDirectorSale50$71K
5 Aug 2026SaleRobert W. Dean IIInterim CFOInterim CFOSale105$141K
3 Aug 2026SaleMaurice SciammasEVP, WW Sales & MarketingEVP, WW Sales & MarketingSale30$40K
15 Jul 2026SaleMaurice SciammasEVP, WW Sales & MarketingEVP, WW Sales & MarketingSale15,000$20M
1 Jul 2026SaleMaurice SciammasEVP, WW Sales & MarketingEVP, WW Sales & MarketingSale30$41K
1 Jun 2026SaleMaurice SciammasEVP, WW Sales & MarketingEVP, WW Sales & MarketingSale30$46K

Showing 10 of 59 trades

Source: SEC insider transactions data sets, Monolithic Power Systems' Form 4 filings

Trades by members of Congress and officials

Trades members of Congress and senior executive branch officials disclosed, including their families'. Amounts are filed as ranges.

Trades from 20 Oct 2023 to 20 Oct 2026

8 people disclosed 9 purchases and 13 sales of Monolithic Power Systems stock since October 2023.

DateMember or officialTypeAmount
5 Jun 2026Byron Donalds (House, R-FL)House, R-FL 路 SoldSale$1,001 to $15,000$1K to $15K
5 Jun 2026Byron Donalds (House, R-FL)House, R-FL 路 SoldSale$1,001 to $15,000$1K to $15K
16 Apr 2026Markwayne Mullin (Secretary)Secretary 路 SoldSale$15,001 to $50,000$15K to $50K
15 Apr 2026Markwayne Mullin (Secretary)Secretary 路 SoldSale$50,001 to $100,000$50K to $100K
9 Apr 2026Donald J Trump (President)President 路 SoldSale$250,001 to $500,000$250K to $500K
23 Mar 2026Donald J Trump (President)President 路 BoughtPurchase$1,001 to $15,000$1K to $15K
4 Feb 2026Markwayne Mullin (Senate, R-OK)Senate, R-OK 路 BoughtPurchase$15,001 to $50,000$15K to $50K
29 Jan 2026Rohit Khanna (House, D-CA)House, D-CA 路 SoldSale$1,001 to $15,000$1K to $15K
23 Jan 2026Rohit Khanna (House, D-CA)House, D-CA 路 BoughtPurchase$1,001 to $15,000$1K to $15K
5 Jan 2026Markwayne Mullin (Senate, R-OK)Senate, R-OK 路 BoughtPurchase$15,001 to $50,000$15K to $50K

Showing 10 of 22 trades

Source: House, Senate and OGE disclosures via the Congress trading monitor

Not on file: no director or officer shared with another S&P 500 company and no WARN layoff notices under its own name since October 2023.