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SEC Form 4 research

MONOLITHIC POWER SYSTEMS INC insider transactions

Inspect MONOLITHIC POWER SYSTEMS INC's public SEC insider acquisitions and sales, reporting owners and source receipts.

As of 2026-10-15T08:02:39.132Z

Issuer CIK
0001280452
Reporting owners
22
Officers and directors
20
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What is a Form 4?

Animation: what a Form 4 is, shown with one real example. Sonic Automotive (SAH) reporting owner Paul P. Rusnak bought 13,701 shares at $59.78 on Wednesday, October 7, 2026, transaction code P, an open-market purchase (S is a sale and A is an award from the company). A timeline marks the SEC's two-business-day filing deadline, which ends Friday, October 9. The SEC accepted the Form 4 at 4:33:21 PM ET on October 9, and NexusTrade treats it as public one minute later, at 4:34:21 PM ET. A lamp for NexusTrade's InsiderTrades indicator stays off from the trade date until that moment, then counts one purchase worth 13,701 × $59.78 = $819,045.78.
In this example the shares were bought on Oct 7, 2026, and NexusTrade's InsiderTrades indicator can count the purchase starting at 4:34:21 PM ET on Oct 9, one minute after the SEC accepted the Form 4.

A Form 4 is the SEC filing a company insider, such as an officer, director or 10% owner, uses to report a trade in the company's stock, generally within two business days. The animation follows one real filing as an example: Paul P. Rusnak's purchase of Sonic Automotive (SAH) shares on October 7, 2026.

The same reading applies to every row on this page. The trade date is when the shares changed hands. The available date is when NexusTrade treats the filing as public, and a NexusTrade InsiderTrades indicator counts a purchase (code P) or sale (code S) only from that moment. Code A awards are not counted as purchases.

Read one actual disclosure before using it

Show the table · 1 row, 7 columns

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2026-09-302026-09-28Hsing MichaelS130$1,356.94Not reported

First displayed source row from Recent insider disclosures. The full bounded history and coverage notes remain below.

The displayed observation date is 2026-09-28 and its public availability date is 2026-09-30. Subtracting those calendar dates gives 2 days of disclosure lag. Historical public research can use the record from the availability date, rather than backdating knowledge to the observation date. The calendar-day difference does not assert an intraday publication time.

This row is code S: a sale. A purchase-following rule excludes this sale even if the reported dollar amount is large.

Open the linked original receipts to verify the row, then inspect a second record before drawing a pattern. This public filing observation supplies source evidence, not a completed copy-trading return.

SEC accession 0001214659-26-012375 ↗SEC accession 0001214659-26-012375 ↗SEC accession 0001214659-26-012375 ↗

Recent insider disclosures

Inspect all 33 displayed rows: Recent insider disclosures

This table includes purchases, sales and awards in the public filing record. Awards and open-market purchases are distinct transaction codes. For historical research, use the public availability date to determine when the transaction was knowable.

Read code P as a purchase, S as a sale and A as an award. An award is an acquisition, but it is not an open-market purchase. Open the filing receipt to check the transaction details.

Scroll sideways to compare all columns. Select a heading to sort.

2026-09-302026-09-28Hsing MichaelS130$1,356.94Not reported
2026-09-302026-09-28Hsing MichaelS10,967$1,351.43Not reported
2026-09-302026-09-28Hsing MichaelS6,343$1,347.15Not reported
2026-09-302026-09-28Hsing MichaelS5,783$1,343.76Not reported
2026-09-302026-09-28Hsing MichaelS2,949$1,338.66Not reported
2026-09-302026-09-28Hsing MichaelS1,111$1,333.34Not reported
2026-09-302026-09-28Hsing MichaelS2,121$1,328.54Not reported
2026-09-302026-09-28Hsing MichaelS596$1,323.31Not reported
2026-08-272026-08-24DEAN ROBERT W IIS32$1,297.72Not reported
2026-08-262026-08-24CHANG KUO WEI HERBERTS50$1,281.57Not reported
2026-08-202026-08-17DEAN ROBERT W IIS6$1,413.64Not reported
2026-08-142026-08-11CHANG KUO WEI HERBERTS50$1,420Not reported
2026-08-072026-08-05DEAN ROBERT W IIS105$1,344.27Not reported
2026-08-062026-08-03Sciammas MauriceS30$1,343.94Not reported
2026-07-292026-07-25DEAN ROBERT W IIA1,359$0Not reported
2026-07-182026-07-15Sciammas MauriceS110$1,405.71Not reported
2026-07-182026-07-15Sciammas MauriceS117$1,400.45Not reported
2026-07-182026-07-15Sciammas MauriceS213$1,396.16Not reported
2026-07-182026-07-15Sciammas MauriceS50$1,388.19Not reported
2026-07-182026-07-15Sciammas MauriceS410$1,384.11Not reported
2026-07-182026-07-15Sciammas MauriceS418$1,378.73Not reported
2026-07-182026-07-15Sciammas MauriceS472$1,375.47Not reported
2026-07-182026-07-15Sciammas MauriceS240$1,369.18Not reported
2026-07-182026-07-15Sciammas MauriceS50$1,359.36Not reported
2026-07-182026-07-15Sciammas MauriceS5,640$1,352.95Not reported
2026-07-182026-07-15Sciammas MauriceS1,506$1,348.91Not reported
2026-07-182026-07-15Sciammas MauriceS1,864$1,344.16Not reported
2026-07-182026-07-15Sciammas MauriceS1,460$1,339.59Not reported
2026-07-182026-07-15Sciammas MauriceS776$1,334.59Not reported
2026-07-182026-07-15Sciammas MauriceS464$1,329.3Not reported
2026-07-182026-07-15Sciammas MauriceS409$1,323.93Not reported
2026-07-182026-07-15Sciammas MauriceS274$1,318.42Not reported
2026-07-182026-07-15Sciammas MauriceS527$1,314.03Not reported

Most recent 90-day source activity, up to 50 rows. No rows means no matching recent records, not no historical activity.

Officers and directors in the directory

Inspect all 21 displayed rows: Officers and directors in the directory

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Rao Meera0001480603143
PADVAL UMESH000130084045
Zhou Jeff000148077257
Moyer James C00013086561,818
CHANG KUO WEI HERBERT0001192171136
Xiao Deming0001308647493
Tseng Saria0001312593408
Hsing Michael00013086761,627
Smith-Bogart Karen A00011915486
BLEGEN THEODORE0001415033488
Chiocchi Adriana000129739817
DEAN ROBERT W II00014453005
EARHART ALAN L000124684636
Elmiger Eugen J000156094515
Lee Victor K000129213341
Martinez Carintia00018652131
MCBURNIE DOUGLAS M000124770113
Neely Rick000133819673
Sciammas Maurice0001360833685
Ueunten Paul000141712369
Wynne Eileen00015757061
Rao Meera ↗PADVAL UMESH ↗Zhou Jeff ↗Moyer James C ↗CHANG KUO WEI HERBERT ↗Xiao Deming ↗Tseng Saria ↗Hsing Michael ↗Smith-Bogart Karen A ↗BLEGEN THEODORE ↗Chiocchi Adriana ↗DEAN ROBERT W II ↗EARHART ALAN L ↗Elmiger Eugen J ↗Lee Victor K ↗Martinez Carintia ↗MCBURNIE DOUGLAS M ↗Neely Rick ↗Sciammas Maurice ↗Ueunten Paul ↗Wynne Eileen ↗

Which transactions qualify for the company tracker

The company strategy uses verified officers and directors with qualifying acquisitions at this issuer. Other reporting owners may appear in source records without becoming strategy signals.

Strategy eligibility is held while filing coverage is unresolved.

Historical follower simulations are separate from these source transactions. They do not establish live trading results.