SCIAMMAS, MAURICE
EVP, WW Sales & Marketing
- Shares
- 30
- % company
- <0.01%
- Price
- $1,534
- Value
- $46,019
Filed Jun 1, 2026
Methodology published · Market data, model notes, and corrections process are public · Data policy · Corrections policy
NASDAQ · TECHNOLOGY · Holders
Monolithic Power Systems Inc (MPWR) Institutional Ownership & Insider Trading History
Recent insider purchases and sales for MPWR from Form 4 filings. Institutional holdings surface here when ownership sources publish.
Section freshness
Price Jun 23, 4:00 PM EDT · Statements Mar 30, 8:00 PM EDT
Source timingDetailsHide
Data freshness
Prices update fastest. Fundamentals, analyst data, and news update on their own schedules, so check these timestamps before comparing signals.
Price time means the latest available trade or regular-market close. Other times show when that section was checked or published.
PriceLive
Last traded •
Source: Market data provider
Fundamentalsevery 1 day
Provider checked •
Source: Market data provider
Analystevery 1 day
Provider checked •
Source: Market data provider
Newsevery 15 min
Latest item •
Source: Market data provider
Ownership read
MPWR insider sentiment: Mixed, sale-heavy.
119 sales and 1 purchases appear in the recent Form 4 filings. Use the filters below to separate real buying and selling from option exercises, gifts, awards, and tax withholding.
Insider flow
MPWR
Purchases1.56K
Sales370.76K
Directional bars ignore awards, gifts, conversions, and tax withholding rows.
Top holder
—
Institutional data pending
Insider stance
Mixed, sale-heavy
$455.60M sold / — bought
Latest filing
Jun 1, 2026
Most recent holder or insider filing date
Filings shown
120
0 holder / 120 insider
- Holder rows
- Pending
- Market data source
- Latest filing
- Jun 1, 2026
- Most recent holder or insider filing date
- Increased / initiated
- Pending
- 0 decreased
- Insider rows
- 120
- Market data source
Recent insider transactions
Monolithic Power Systems Inc (MPWR) Form 4 filings
Action codes are translated so open-market buys and sales are separate from awards, gifts, conversions, and tax withholding.
SCIAMMAS, MAURICE
EVP, WW Sales & Marketing
- Shares
- 12.47K
- % company
- 0.03%
- Price
- Not reported
- Value
- Not reported
Filed May 29, 2026
TSENG, SARIA
EVP & General Counsel
- Shares
- 7.57K
- % company
- 0.02%
- Price
- $1,700
- Value
- $12,860,500
Filed May 27, 2026
DEAN, ROBERT W II
Interim CFO
- Shares
- 22
- % company
- <0.01%
- Price
- $1,650
- Value
- $36,290
Filed May 26, 2026
ZHOU, JEFF
Director
- Shares
- 486
- % company
- <0.01%
- Price
- $1,680
- Value
- $816,480
Filed May 26, 2026
TSENG, SARIA
EVP & General Counsel
- Shares
- 200
- % company
- <0.01%
- Price
- Not reported
- Value
- Not reported
Filed May 22, 2026
TSENG, SARIA
EVP & General Counsel
- Shares
- 5.00K
- % company
- 0.01%
- Price
- $1,586
- Value
- $7,932,150
Filed May 22, 2026
HSING, MICHAEL
Director, CEO
- Shares
- 352
- % company
- <0.01%
- Price
- $1,518
- Value
- $534,389
Filed May 18, 2026
HSING, MICHAEL
Director, CEO
- Shares
- 130
- % company
- <0.01%
- Price
- $1,521
- Value
- $197,786
Filed May 18, 2026
DEAN, ROBERT W II
Interim CFO
- Shares
- 4
- % company
- <0.01%
- Price
- $1,563
- Value
- $6,253
Filed May 18, 2026
HSING, MICHAEL
Director, CEO
- Shares
- 5.74K
- % company
- 0.01%
- Price
- $1,483
- Value
- $8,505,160
Filed May 18, 2026
HSING, MICHAEL
Director, CEO
- Shares
- 4.08K
- % company
- <0.01%
- Price
- $1,477
- Value
- $6,028,951
Filed May 18, 2026
| # | Insider | % company | Action | Shares | Price | Value | Filing date |
|---|---|---|---|---|---|---|---|
| 1 | SCIAMMAS, MAURICE EVP, WW Sales & Marketing | <0.01% | SaleOpen-market or direct sale reported on Form 4. | 30 | $1,534 | $46,019 | Jun 1, 2026 |
| 2 | SCIAMMAS, MAURICE EVP, WW Sales & Marketing | 0.03% | SaleOpen-market or direct sale reported on Form 4. | 12.47K | Not reported | Not reported | May 29, 2026 |
| 3 | TSENG, SARIA EVP & General Counsel | 0.02% | SaleOpen-market or direct sale reported on Form 4. | 7.57K | $1,700 | $12,860,500 | May 27, 2026 |
| 4 | DEAN, ROBERT W II Interim CFO | <0.01% | SaleOpen-market or direct sale reported on Form 4. | 22 | $1,650 | $36,290 | May 26, 2026 |
| 5 | ZHOU, JEFF Director | <0.01% | SaleOpen-market or direct sale reported on Form 4. | 486 | $1,680 | $816,480 | May 26, 2026 |
| 6 | TSENG, SARIA EVP & General Counsel | <0.01% | SaleOpen-market or direct sale reported on Form 4. | 200 | Not reported | Not reported | May 22, 2026 |
| 7 | TSENG, SARIA EVP & General Counsel | 0.01% | SaleOpen-market or direct sale reported on Form 4. | 5.00K | $1,586 | $7,932,150 | May 22, 2026 |
| 8 | HSING, MICHAEL Director, CEO | <0.01% | SaleOpen-market or direct sale reported on Form 4. | 352 | $1,518 | $534,389 | May 18, 2026 |
| 9 | HSING, MICHAEL Director, CEO | <0.01% | SaleOpen-market or direct sale reported on Form 4. | 130 | $1,521 | $197,786 | May 18, 2026 |
| 10 | DEAN, ROBERT W II Interim CFO | <0.01% | SaleOpen-market or direct sale reported on Form 4. | 4 | $1,563 | $6,253 | May 18, 2026 |
| 11 | HSING, MICHAEL Director, CEO | 0.01% | SaleOpen-market or direct sale reported on Form 4. | 5.74K | $1,483 | $8,505,160 | May 18, 2026 |
| 12 | HSING, MICHAEL Director, CEO | <0.01% | SaleOpen-market or direct sale reported on Form 4. | 4.08K | $1,477 | $6,028,951 | May 18, 2026 |
Showing 12 of 120 matching Form 4 rows. Percent of company uses current shares outstanding when available.Load more insiders
Frequently asked
Common questions.
Who are the largest MPWR shareholders?
Monolithic Power Systems Inc (MPWR) institutional holders are ranked by reported share count when ownership data publishes filing rows.
What is institutional ownership of MPWR?
Monolithic Power Systems Inc (MPWR) institutional ownership appears when filing-based market data returns holder rows. TECHi does not fill unavailable ownership fields with placeholder shareholders.
Where can I see Monolithic Power Systems Inc insider transactions?
Monolithic Power Systems Inc (MPWR) has 120 Form 4 insider transactions on file, most recently on Jun 1, 2026, separated into purchases, sales, option exercises, awards, gifts, and tax withholding so administrative transactions are distinguished from open-market trades.
Are MPWR insiders buying or selling?
Recent MPWR insider activity reads Mixed, sale-heavy: 119 sales and 1 purchases. Awards, gifts, conversions, and tax withholding are listed separately because they do not carry the same signal as open-market trades.
Who is the most active MPWR insider?
HSING, MICHAEL is the most active MPWR insider by absolute share movement, with 194,923 shares moving across the filing history. Review the action labels before treating that activity as buying or selling.