QUANTERIX CORP

Ticker: QTRX CUSIP: 74766Q101 Class: Common Stock

North Star Investment Management Corp.'s Holding History (CIK: 0001342857)

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

Q4 2025

Shares 100 Value ($000) $1 Avg Close $6.21 Range $4.50 - $7.88

Q3 2025

Shares 100 Value ($000) $1 Avg Close $5.32 Range $4.15 - $7.09

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2025	100	$1	$6.21	$4.50 - $7.88
Q3 2025	100	$1	$5.32	$4.15 - $7.09