ION GEOPHYSICAL CORP

CUSIP: 462044108 Class: COM

HighTower Advisors, LLC's Holding History (CIK: 0001462245)

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

Q4 2015
Shares 200,313 Value ($000) $101 Avg Close — Range —
Q3 2015
Shares 200,313 Value ($000) $78 Avg Close — Range —