CYTEK BIOSCIENCES INC

Ticker: CTKB CUSIP: 23285D109 Class: Common Stock

GROUP ONE TRADING, L.P.'s Holding History (CIK: 0000932540)

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

Q4 2025

Shares 1,500 Value ($000) $8 Avg Close $4.64 Range $3.45 - $6.18

Q1 2024

Shares 8,377 Value ($000) $56 Avg Close $7.91 Range $6.16 - $9.33

Q4 2023

Shares 7,493 Value ($000) $68 Avg Close $6.29 Range $3.80 - $9.87

Q4 2022

Shares 61 Value ($000) $1 Avg Close $13.44 Range $9.59 - $15.90

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2025	1,500	$8	$4.64	$3.45 - $6.18
Q1 2024	8,377	$56	$7.91	$6.16 - $9.33
Q4 2023	7,493	$68	$6.29	$3.80 - $9.87
Q4 2022	61	$1	$13.44	$9.59 - $15.90