DOCUMENT SEC SYS INC

CUSIP: 25614T200 Class: COM NEW

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

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

Q1 2020
Shares 3,100 Value ($000) $1 Avg Close — Range —
Q2 2019
Shares 100 Value ($000) $0 Avg Close — Range —
Q1 2018
Shares 794 Value ($000) $1 Avg Close — Range —
Q4 2017
Shares 28,575 Value ($000) $51 Avg Close — Range —