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ION GEOPHYSICAL CORP
ION GEOPHYSICAL CORP. Institutional holdings reported to the SEC.

Institutional Holders (2014Q1)
Portfolio Summary: 174 Institutional holders with a total value of $441,893,970.
#
Manager Name
Shares
Value ($)
%
Options
Notes
151 Pinnacle Summer Investments, Inc. 5,000 22,000 0.00%
152 MANAGED ACCOUNT ADVISORS LLC 4,788 20,000 0.00%
153 TEACHER RETIREMENT SYSTEM OF TEXAS 4,855 20,000 0.00%
154 Creative Planning 4,600 19,000 0.00%
155 BlackRock Finance, Inc. 4,347 18,000 0.00%
156 CANADA LIFE ASSURANCE Co 4,075 17,000 0.00%
157 Spot Trading L.L.C 4,091 17,000 0.00%
158 PEAK6 Group LLC 3,700 16,000 0.00% Call
159 BROWN BROTHERS HARRIMAN & CO 3,500 15,000 0.00%
160 Spot Trading L.L.C 2,800 12,000 0.00% Put
161 LADENBURG THALMANN FINANCIAL SERVICES INC. 2,500 11,000 0.00%
162 BARCLAYS PLC 2,100 8,000 0.00% Call
163 GLENMEDE TRUST CO NA 1,500 6,000 0.00%
164 Parallax Volatility Advisers, L.P. 856 4,000 0.00%
165 B. Riley Wealth Management, Inc. 1,000 4,000 0.00%
166 PIEDMONT INVESTMENT ADVISORS INC 576 2,424 0.00%
167 ROYAL BANK OF CANADA 500 2,000 0.00%
168 PNC FINANCIAL SERVICES GROUP, INC. 520 2,000 0.00%
169 HABERER REGISTERED INVESTMENT ADVISOR INC 300 1,000 0.00% SH
170 Tower Research Capital LLC (TRC) 122 1,000 0.00%
171 ENTERPRISE FINANCIAL SERVICES CORP 228 1,000 0.00%
172 Walleye Trading LLC 100 0 0.00% Call
173 US BANCORP \DE\ 90 0 0.00%
174 Gemmer Asset Management LLC 116 0 0.00%
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From 2023-01-03 onward, the SEC requires values to be reported in nearest dollars. Earlier filings reported values in thousands; therefore, positions shown as $0 in older filings may represent actual values between $0–$999.