Monolithic Power Sys (MPWR): Congress and insider trades

Who in Congress and inside the company traded MPWR, when each filing appeared, and what buying after each one would have earned against the S&P 500.

Key Facts

  • Monolithic Power Sys (MPWR) is a listed stock on NASDAQ.
  • 5 members of Congress filed 16 buys and 13 sells of MPWR, the latest published 2026-08-12 (12 August 2026).
  • Insiders filed 0 open market buys worth $0 and 24 sells worth $171M, the latest filed 2026-08-26 (26 August 2026).
  • Across 13 scored buys, Congress averaged +9.4% against the S&P 500 (SPY) over the 90 days after disclosure, with 69% of them ahead of the index. That result is not distinguishable from luck.
  • Data as of 2026-09-29 (29 September 2026).
Congress buys 16 5 members
Congress sells 13
Insider buys 0 $0
Insider sells 24 $171M
Congress buys vs S&P, 90d +9.4% 13 scored buys
Insider buys vs S&P, 90d n/a 0 scored buys

Congress trades in MPWR

as of 2026-08-12
  1. Ro Khanna19 trades
  2. Tommy Tuberville4 trades
  3. Markwayne Mullin3 trades
  4. Byron Donalds2 trades
  5. Rob Bresnahan1 trade
Congress trades in MPWR, newest first.
FiledMemberTypeSizeDays to file90 day vs S&P
12 Aug 2026 Ro Khanna (D-CA) buy 1K–15K 11 n/a
5 Aug 2026 Tommy Tuberville (R-AL) sell 1K–15K 824 n/a
16 Jul 2026 Byron Donalds (R-FL) sell 1K–15K 40 n/a
16 Jul 2026 Byron Donalds (R-FL) sell 1K–15K 40 n/a
8 Jul 2026 Ro Khanna (D-CA) buy 1K–15K 18 n/a
11 Jun 2026 Ro Khanna (D-CA) buy 15K–50K 18 -27.1%
9 Apr 2026 Ro Khanna (D-CA) sell 1K–15K 28 n/a
12 Mar 2026 Ro Khanna (D-CA) buy 1K–15K 32 +39.6%
2 Mar 2026 Markwayne Mullin (R-OK) buy 15K–50K 26 +32.0%
4 Feb 2026 Markwayne Mullin (R-OK) buy 15K–50K 30 +34.6%
4 Feb 2026 Markwayne Mullin (R-OK) buy 15K–50K 30 +34.6%
15 May 2025 Ro Khanna (D-CA) sell 1K–15K 19 n/a
9 May 2025 Rob Bresnahan (R-PA) buy 1K–15K 30 +4.0%
16 Nov 2023 Tommy Tuberville (R-AL) buy 1K–15K 30 +24.4%
10 Nov 2023 Ro Khanna (D-CA) sell 15K–50K 13 n/a
12 Jul 2023 Ro Khanna (D-CA) sell 1K–15K 26 n/a
12 May 2023 Tommy Tuberville (R-AL) sell 1K–15K 39 n/a
9 Feb 2023 Ro Khanna (D-CA) buy 1K–15K 29 -20.2%
7 Dec 2022 Ro Khanna (D-CA) sell 1K–15K 33 n/a
7 Dec 2022 Ro Khanna (D-CA) buy 1K–15K 34 +30.1%
17 Nov 2022 Ro Khanna (D-CA) sell 1K–15K 21 n/a
12 Oct 2022 Ro Khanna (D-CA) sell 1K–15K 8 n/a
12 Oct 2022 Ro Khanna (D-CA) buy 1K–15K 31 +11.4%
11 Jul 2022 Ro Khanna (D-CA) sell 1K–15K 20 n/a
15 Jun 2022 Ro Khanna (D-CA) buy 1K–15K 31 +3.1%
12 May 2022 Ro Khanna (D-CA) buy 1K–15K 25 +15.2%
9 Feb 2022 Ro Khanna (D-CA) sell 1K–15K 28 n/a
16 Oct 2021 Tommy Tuberville (R-AL) buy 1K–15K 15 -14.8%
16 Sep 2021 Ro Khanna (D-CA) buy 1K–15K 22 -10.0%

Insider trades in MPWR

as of 2026-08-26
Open market insider trades in MPWR, newest first.
FiledInsiderTypeSharesPriceValue90 day vs S&P
26 Aug 2026 DEAN ROBERT W II sell 32 $1297.72 $41.5K n/a
25 Aug 2026 CHANG KUO WEI HERBERT sell 50 $1281.57 $64.1K n/a
19 Aug 2026 DEAN ROBERT W II sell 6 $1413.64 $8.5K n/a
13 Aug 2026 CHANG KUO WEI HERBERT sell 50 $1420.00 $71.0K n/a
6 Aug 2026 DEAN ROBERT W II sell 105 $1344.27 $141K n/a
5 Aug 2026 Sciammas Maurice sell 30 $1343.94 $40.3K n/a
17 Jul 2026 Sciammas Maurice sell 15,000 $1349.73 $20M n/a
6 Jul 2026 Sciammas Maurice sell 30 $1351.61 $40.5K n/a
3 Jun 2026 Sciammas Maurice sell 30 $1533.95 $46.0K n/a
29 May 2026 Tseng Saria sell 7,565 $1700.00 $13M n/a
28 May 2026 DEAN ROBERT W II sell 22 $1649.56 $36.3K n/a
27 May 2026 Tseng Saria sell 5,000 $1586.43 $7.9M n/a
27 May 2026 Zhou Jeff sell 486 $1680.00 $816K n/a
20 May 2026 Hsing Michael sell 40,000 $1482.75 $59M n/a
20 May 2026 DEAN ROBERT W II sell 4 $1563.28 $6.3K n/a
19 May 2026 Sciammas Maurice sell 12,000 $1561.40 $19M n/a
6 May 2026 Zhou Jeff sell 500 $1650.00 $825K n/a
6 May 2026 Zhou Jeff sell 1,014 $1587.06 $1.6M n/a
10 Apr 2026 Tseng Saria sell 8,963 $1305.22 $12M n/a
8 Apr 2026 Tseng Saria sell 7,636 $1167.95 $8.9M n/a
3 Apr 2026 Sciammas Maurice sell 30 $1116.44 $33.5K n/a
3 Apr 2026 Tseng Saria sell 1,400 $1133.52 $1.6M n/a
1 Apr 2026 Tseng Saria sell 25,674 $1010.50 $26M n/a
24 Mar 2026 Sciammas Maurice sell 30 $1095.07 $32.9K n/a

Frequently asked questions

Who has bought MPWR?

16 Congress buys by 5 members and 0 insider buys are on file. The tables on this page list every one.

Did buying MPWR after a disclosure beat the market?

Across 13 scored buys, Congress averaged +9.4% against the S&P 500 (SPY) over the 90 days after disclosure, with 69% of them ahead of the index. That result is not distinguishable from luck. A single stock is a small sample.

Sources: Congressional trades: STOCK Act disclosures, collected from CapitolTrades. Insider trades: SEC Form 4 filings, collected from Finviz. Prices: Yahoo Finance daily adjusted closes. Data as of 2026-09-29 (29 September 2026). About these sources.

Not investment advice. Past disclosed trades do not predict future returns. Disclosures are published late, so the trades shown are ones you could only have copied after the fact. Talk to a licensed adviser before you invest.