IMPERVA INC

CUSIP: 45321L100 Class: COM

NISA INVESTMENT ADVISORS, LLC's Holding History (CIK: 0000937615)

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

Q4 2018
Shares 240 Value ($000) $13 Avg Close — Range —
Q3 2018
Shares 240 Value ($000) $11 Avg Close — Range —
Q2 2018
Shares 260 Value ($000) $13 Avg Close — Range —
Q1 2018
Shares 260 Value ($000) $11 Avg Close — Range —
Q4 2017
Shares 310 Value ($000) $12 Avg Close — Range —
Q3 2017
Shares 310 Value ($000) $13 Avg Close — Range —
Q2 2017
Shares 310 Value ($000) $15 Avg Close — Range —
Q1 2017
Shares 210 Value ($000) $9 Avg Close — Range —
Q4 2016
Shares 400 Value ($000) $15 Avg Close — Range —
Q3 2016
Shares 400 Value ($000) $21 Avg Close — Range —
Q2 2016
Shares 400 Value ($000) $17 Avg Close — Range —
Q1 2016
Shares 400 Value ($000) $20 Avg Close — Range —