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MPWR Monolithic Power Systems, Inc.

Insider figures are trailing 90 days, open-market Form 4 only. Institutional figures are the latest reported quarter. These windows are not simultaneous.

-$20.6M net selling - trailing 90 days

0 buyers - 3 unique sellers

Historical context: most recent complete month (2026-08) is the 80th percentile of this ticker's monthly net P/S flow over 23 complete months (limited history). Lower percentiles are more selling; higher are more buying.

Institutional activity: not available - insufficient comparable institutions for the latest complete quarter.

open-market Form 4 only - grants, exercises, tax withholding excluded. ~ derived from SEC-reported shares x price.

Insider net $ (monthly)open-market Form 4 only - grants, exercises, tax withholding excluded$500.0M$250.0M$0-$250.0M-$500.0M2024-10 -$12.5M2024-11 -$5.0M2024-12 -$1.5M2025-01 -$2.5M2025-02 -$20.1M2025-03 $02025-04 $02025-05 -$8.6M2025-06 $02025-07 -$4.5M2025-08 -$53.0M2025-09 -$16.1M2025-10 -$21.3M2025-11 -$147.8M2025-12 -$3.5M2026-01 -$3.1M2026-02 -$234.9M2026-03 -$26.0M2026-04 -$22.1M2026-05 -$172.0M2026-06 -$46K2026-07 -$20.2M2026-08 -$367KOct 24Dec 24Feb 25Apr 25Jun 25Aug 25Oct 25Dec 25Feb 26Apr 26Jun 26Aug 26~ derived from SEC-reported shares x price. Hatched: excluded (implausible price) or unpriced.

Institutional activity: not available - insufficient comparable institutions for the latest complete quarter.

Who is responsible

Insider Role Net activity Rows
Sciammas Maurice EVP, WW Sales & Marketing -~$20.3M 19
DEAN ROBERT W II Interim CFO -~$0.2M 3
CHANG KUO WEI HERBERT -~$0.1M 2

Transactions

Date Insider Role Type Shares Price Value
8/24/2026 DEAN ROBERT W II Interim CFO S -32 1297.72 ~$42K
8/24/2026 CHANG KUO WEI HERBERT S -50 1281.57 ~$64K
8/17/2026 DEAN ROBERT W II Interim CFO S -6 1413.64 ~$8K
8/11/2026 CHANG KUO WEI HERBERT S -50 1420 ~$71K
8/5/2026 DEAN ROBERT W II Interim CFO S -105 1344.27 ~$0.1M
8/3/2026 Sciammas Maurice EVP, WW Sales & Marketing S -30 1343.94 ~$40K
7/15/2026 Sciammas Maurice EVP, WW Sales & Marketing 17 reported sale rows 14950 ~$20.2M
7/1/2026 Sciammas Maurice EVP, WW Sales & Marketing S -30 1351.61 ~$41K
6/1/2026 Sciammas Maurice EVP, WW Sales & Marketing S -30 1533.95 ~$46K
5/27/2026 Tseng Saria EVP & General Counsel S -7565 1700 ~$12.9M
5/26/2026 DEAN ROBERT W II Interim CFO S -22 1649.56 ~$36K
5/26/2026 Zhou Jeff S -486 1680 ~$0.8M
5/22/2026 Tseng Saria EVP & General Counsel S -5000 1586.43 ~$7.9M
5/18/2026 DEAN ROBERT W II Interim CFO S -4 1563.28 ~$6K
5/18/2026 Hsing Michael CEO 13 reported sale rows 40000 ~$59.3M
5/15/2026 Sciammas Maurice EVP, WW Sales & Marketing 8 reported sale rows 12000 ~$18.7M
5/6/2026 Xiao Deming EVP, Global Operations 4 reported sale rows 30000 ~$49.6M
5/6/2026 Zhou Jeff S -500 1650 ~$0.8M
5/6/2026 Elmiger Eugen J 9 reported sale rows 12000 ~$19.0M
5/6/2026 Wynne Eileen S -335 1582.68 ~$0.5M
5/5/2026 Sciammas Maurice EVP, WW Sales & Marketing S -380 1583.81 ~$0.6M
5/5/2026 Zhou Jeff 2 reported sale rows 1014 ~$1.6M
5/4/2026 Sciammas Maurice EVP, WW Sales & Marketing S -30 1588.73 ~$48K
4/8/2026 Tseng Saria EVP & General Counsel 9 reported sale rows 8843 ~$11.5M
4/6/2026 Tseng Saria EVP & General Counsel 8 reported sale rows 7636 ~$8.9M
4/1/2026 Sciammas Maurice EVP, WW Sales & Marketing S -30 1116.44 ~$33K
4/1/2026 Tseng Saria EVP & General Counsel 5 reported sale rows 1400 ~$1.6M
3/30/2026 Tseng Saria EVP & General Counsel 8 reported sale rows 25674 ~$25.9M
3/20/2026 Sciammas Maurice EVP, WW Sales & Marketing S -30 1095.07 ~$33K
2/12/2026 Hsing Michael CEO 11 reported sale rows 31560 ~$36.9M
2/11/2026 Hsing Michael CEO 10 reported sale rows 33000 ~$39.2M
2/11/2026 Sciammas Maurice EVP, WW Sales & Marketing S -200 1179.975 ~$0.2M
2/10/2026 Hsing Michael CEO 9 reported sale rows 34000 ~$38.8M
2/9/2026 Lee Victor K S -400 1212.16 ~$0.5M
2/6/2026 Hsing Michael CEO S -54923 1171.1637 ~$64.3M
2/6/2026 Xiao Deming EVP, Global Operations S -22875 1171.1637 ~$26.8M jointly filed
2/6/2026 Tseng Saria EVP & General Counsel S -22875 1171.1637 ~$26.8M jointly filed
2/6/2026 Sciammas Maurice EVP, WW Sales & Marketing S -22875 1171.1637 ~$26.8M jointly filed
2/6/2026 BLEGEN THEODORE EVP and CFO S -21725 1171.1637 ~$25.4M
2/2/2026 BLEGEN THEODORE EVP and CFO 11 reported sale rows 2360 ~$2.7M
1/2/2026 BLEGEN THEODORE EVP and CFO 10 reported sale rows 2680 ~$2.5M
1/2/2026 Lee Victor K S -600 930.86 ~$0.6M
12/24/2025 Lee Victor K 6 reported sale rows 1000 ~$1.0M
12/1/2025 BLEGEN THEODORE EVP and CFO 6 reported sale rows 2760 ~$2.5M
11/26/2025 Tseng Saria EVP & General Counsel 9 reported sale rows 20000 ~$18.5M
11/25/2025 Tseng Saria EVP & General Counsel 18 reported sale rows 19840 ~$17.9M
11/25/2025 CHANG KUO WEI HERBERT S -100 896.97 ~$90K
11/24/2025 Sciammas Maurice EVP, WW Sales & Marketing S -3976 895.23 ~$3.6M
11/21/2025 CHANG KUO WEI HERBERT S -100 873.97 ~$87K
11/19/2025 Sciammas Maurice EVP, WW Sales & Marketing 24 reported sale rows 35000 ~$30.8M
11/12/2025 Hsing Michael CEO 18 reported sale rows 36597 ~$35.3M
11/11/2025 Hsing Michael CEO 17 reported sale rows 40000 ~$38.3M
11/5/2025 Sciammas Maurice EVP, WW Sales & Marketing S -200 986.81 ~$0.2M
11/3/2025 BLEGEN THEODORE EVP and CFO 19 reported sale rows 2840 ~$2.9M
10/24/2025 Tseng Saria EVP & General Counsel S -1300 1087.62 ~$1.4M
10/16/2025 Tseng Saria EVP & General Counsel 2 reported sale rows 2812 ~$2.9M
10/15/2025 Tseng Saria EVP & General Counsel S -14028 1016.18 ~$14.3M
10/1/2025 BLEGEN THEODORE EVP and CFO 13 reported sale rows 3000 ~$2.7M
9/18/2025 Tseng Saria EVP & General Counsel S -14510 914.45 ~$13.3M
9/18/2025 Martinez Carintia S -1400 900 ~$1.3M
9/2/2025 BLEGEN THEODORE EVP and CFO 6 reported sale rows 1900 ~$1.5M
8/29/2025 Elmiger Eugen J 4 reported sale rows 2500 ~$2.1M
8/27/2025 Zhou Jeff S -193 870 ~$0.2M
8/15/2025 Hsing Michael CEO 11 reported sale rows 20231 ~$16.8M
8/13/2025 Zhou Jeff S -400 850 ~$0.3M
8/12/2025 Zhou Jeff S -200 830 ~$0.2M
8/1/2025 Xiao Deming EVP, Global Operations S -39999 780 ~$31.2M
8/1/2025 BLEGEN THEODORE EVP and CFO S -3000 750 ~$2.3M
7/1/2025 BLEGEN THEODORE EVP and CFO S -6000 750 ~$4.5M
5/13/2025 CHANG KUO WEI HERBERT S -50 738 ~$37K
5/12/2025 CHANG KUO WEI HERBERT S -100 698 ~$70K
5/12/2025 Sciammas Maurice EVP, WW Sales & Marketing S -12000 701 ~$8.4M
5/8/2025 CHANG KUO WEI HERBERT S -100 650 ~$65K
2/18/2025 Hsing Michael CEO S -5200 700 ~$3.6M
2/10/2025 Sciammas Maurice EVP, WW Sales & Marketing S -662 717.1006 ~$0.5M jointly filed
2/10/2025 Hsing Michael CEO S -2594 717.1 ~$1.9M
2/10/2025 BLEGEN THEODORE EVP and CFO S -532 717.1007 ~$0.4M
2/10/2025 Tseng Saria EVP & General Counsel S -663 717.1004 ~$0.5M
2/10/2025 Xiao Deming EVP, Global Operations S -662 717.1006 ~$0.5M jointly filed
2/7/2025 Sciammas Maurice EVP, WW Sales & Marketing 4 reported sale rows 7000 ~$4.9M
2/7/2025 Hsing Michael CEO S -11964 700 ~$8.4M
1/24/2025 Hsing Michael CEO S -3636 700 ~$2.5M
12/9/2024 BLEGEN THEODORE EVP and CFO S -2500 600 ~$1.5M
11/8/2024 Tseng Saria EVP & General Counsel S -866 765.14 ~$0.7M jointly filed
11/8/2024 Hsing Michael CEO S -2812 765.15 ~$2.2M
11/8/2024 Xiao Deming EVP, Global Operations S -866 765.14 ~$0.7M jointly filed
11/8/2024 BLEGEN THEODORE EVP and CFO S -734 765.15 ~$0.6M
11/8/2024 Sciammas Maurice EVP, WW Sales & Marketing S -866 765.14 ~$0.7M jointly filed
11/1/2024 BLEGEN THEODORE EVP and CFO 11 reported sale rows 2150 ~$1.7M
10/7/2024 Sciammas Maurice EVP, WW Sales & Marketing 11 reported sale rows 11000 ~$10.2M
10/1/2024 BLEGEN THEODORE EVP and CFO 19 reported sale rows 2500 ~$2.3M