HSING MICHAEL (CEO) sold 3.5% of their position (30K shares) of MONOLITHIC POWER SYSTEMS, INC. on the open market

Open‑market sale worth $40.35M — a minor trim. Review remaining holdings and any 10b5‑1 plan disclosures.

S · 8 sales

HSING MICHAEL

Filed: 9/30/2026ACC: 0001214659-26-012375

InsiderHSING MICHAELCIK 1308676

→

IssuerMONOLITHIC POWER SYSTEMS, INC.CIK 1280452

DirectorOfficer· CEO

Since Jul 2018

-30K

Net shares

Net seller

$40.35M

Total sold

Open market trades

0B · 8S

Total transactions

30K disposed

Non-Derivative Transactions8

Common Stock

Direct

S · Sale

−596.00

Price / share

$1.32K

Trade value

$788.69K

% of position

0.1%

9/28/2026

848.26K→847.67K

Common Stock

Direct

S · Sale

−2.12K

Price / share

$1.33K

Trade value

$2.82M

% of position

0.3%

9/28/2026

847.67K→845.55K

Common Stock

Direct

S · Sale

−1.11K

Price / share

$1.33K

Trade value

$1.48M

% of position

0.1%

9/28/2026

845.55K→844.44K

Common Stock

Direct

S · Sale

−2.95K

Price / share

$1.34K

Trade value

$3.95M

% of position

0.3%

9/28/2026

844.44K→841.49K

Common Stock

Direct

S · Sale

−5.78K

Price / share

$1.34K

Trade value

$7.77M

% of position

0.7%

9/28/2026

841.49K→835.70K

Common Stock

Direct

S · Sale

−6.34K

Price / share

$1.35K

Trade value

$8.54M

% of position

0.8%

9/28/2026

835.70K→829.36K

Common Stock

Direct

S · Sale

−10.97K

Price / share

$1.35K

Trade value

$14.82M

% of position

1.3%

9/28/2026

829.36K→818.39K

Common Stock

Direct

S · Sale

−130.00

Price / share

$1.36K

Trade value

$176.40K

% of position

0.0%

9/28/2026

818.39K→818.26K

Total

Net shares

−30K

Net value

-$40.35M

Security	Date	Type	Shares	Price / Share	Trade Value	% of Position	Held Before	Held After
Common Stock Direct	9/28/2026	S · Sale	−596.00	$1.32K	$788.69K	0.1%	848.26K	847.67K
Common Stock Direct	9/28/2026	S · Sale	−2.12K	$1.33K	$2.82M	0.3%	847.67K	845.55K
Common Stock Direct	9/28/2026	S · Sale	−1.11K	$1.33K	$1.48M	0.1%	845.55K	844.44K
Common Stock Direct	9/28/2026	S · Sale	−2.95K	$1.34K	$3.95M	0.3%	844.44K	841.49K
Common Stock Direct	9/28/2026	S · Sale	−5.78K	$1.34K	$7.77M	0.7%	841.49K	835.70K
Common Stock Direct	9/28/2026	S · Sale	−6.34K	$1.35K	$8.54M	0.8%	835.70K	829.36K
Common Stock Direct	9/28/2026	S · Sale	−10.97K	$1.35K	$14.82M	1.3%	829.36K	818.39K
Common Stock Direct	9/28/2026	S · Sale	−130.00	$1.36K	$176.40K	0.0%	818.39K	818.26K
Total			−30K		-$40.35M

Derivative Transactions0

No derivative transactions reported

Non-Derivative Holdings (Post-Transaction)2

Common Stock

Indirect

Shares owned133.04K

Common Stock

Indirect

Shares owned12.82K

Total

145.87K indirect145.87K

Security Title	Shares Owned	Ownership Type
Common Stock	133.04K	Indirect
Common Stock	12.82K	Indirect
Total	145.87K	145.87K indirect

Derivative Holdings (Post-Transaction)0

No derivative holdings reported