QUANTUM SI INC

Ticker: QSI CUSIP: 74765K105 Class: Common Stock

Vanguard Personalized Indexing Management, LLC's Holding History (CIK: 0001767306)

Note: Option positions (PUT/CALL) are excluded.

Q4 2025

Shares 23,799 Value ($000) $26 Avg Close $1.63 Range $1.07 - $3.10

Q3 2025

Shares 25,193 Value ($000) $36 Avg Close $1.45 Range $0.95 - $2.18

Q2 2025

Shares 24,091 Value ($000) $47 Avg Close $1.48 Range $1.02 - $2.15

Q1 2025

Shares 23,477 Value ($000) $28 Avg Close $1.92 Range $1.12 - $5.77

Q4 2024

Shares 19,945 Value ($000) $54 Avg Close $1.17 Range $0.61 - $4.14

Q3 2024

Shares 16,333 Value ($000) $14 Avg Close $0.97 Range $0.79 - $1.26

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2025	23,799	$26	$1.63	$1.07 - $3.10
Q3 2025	25,193	$36	$1.45	$0.95 - $2.18
Q2 2025	24,091	$47	$1.48	$1.02 - $2.15
Q1 2025	23,477	$28	$1.92	$1.12 - $5.77
Q4 2024	19,945	$54	$1.17	$0.61 - $4.14
Q3 2024	16,333	$14	$0.97	$0.79 - $1.26