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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
1 Invesco Ltd. 32,588,760 137,199,000 31.05%
2 VANGUARD GROUP INC 8,715,856 36,693,000 8.30%
3 WELLS FARGO & COMPANY/MN 7,675,453 32,313,000 7.31%
4 BlackRock Fund Advisors 7,403,069 31,167,000 7.05%
5 BlackRock Institutional Trust Company, N.A. 3,924,959 16,524,000 3.74%
6 DIMENSIONAL FUND ADVISORS LP 3,588,307 15,106,000 3.42%
7 STATE STREET CORP 3,426,364 14,425,000 3.26%
8 Neuberger Berman Group LLC 2,933,602 12,350,000 2.79%
9 AMERIPRISE FINANCIAL INC 2,313,057 9,738,000 2.20%
10 Allianz Asset Management GmbH 2,022,148 8,513,000 1.93%
11 NORTHERN TRUST CORP 1,789,433 7,533,000 1.70%
12 NORGES BANK 1,739,115 7,321,000 1.66%
13 Bank of New York Mellon Corp 1,480,682 6,234,000 1.41%
14 ROYCE & ASSOCIATES LP 1,178,200 4,960,000 1.12%
15 TIAA CREF INVESTMENT MANAGEMENT LLC 1,102,988 4,644,000 1.05%
16 RENAISSANCE TECHNOLOGIES LLC 984,257 4,144,000 0.94%
17 BOGLE INVESTMENT MANAGEMENT L P /DE/ 916,950 3,860,000 0.87%
18 MORGAN STANLEY 845,437 3,560,000 0.81%
19 PRINCIPAL FINANCIAL GROUP INC 774,236 3,260,000 0.74%
20 Archer Capital Management, L.P. 736,200 3,099,000 0.70% Put
21 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 700,009 2,948,000 0.67%
22 GEODE CAPITAL MANAGEMENT, LLC 697,131 2,934,000 0.66%
23 BLACKROCK ADVISORS LLC 686,001 2,888,000 0.65%
24 DEUTSCHE BANK AG\ 613,151 2,579,000 0.58%
25 Counsel Portfolio Services Inc. 577,175 2,430,000 0.55%
26 BlackRock Investment Management, LLC 507,478 2,136,000 0.48%
27 CALIFORNIA PUBLIC EMPLOYEES RETIREMENT SYSTEM 483,900 2,017,000 0.46%
28 PANAGORA ASSET MANAGEMENT INC 477,643 2,011,000 0.46%
29 CITADEL ADVISORS LLC 433,647 1,826,000 0.41%
30 NEW YORK STATE TEACHERS RETIREMENT SYSTEM 415,082 1,747,000 0.40%
31 D. E. Shaw & Co., Inc. 412,438 1,736,000 0.39%
32 Pine River Capital Management L.P. 400,000 1,683,000 0.38% Put
33 Pine River Capital Management L.P. 400,000 1,683,000 0.38% Call
34 TFS CAPITAL LLC 379,203 1,596,000 0.36%
35 WELLINGTON MANAGEMENT GROUP LLP 355,909 1,498,000 0.34%
36 JACOBS LEVY EQUITY MANAGEMENT, INC 348,101 1,466,000 0.33%
37 PRUDENTIAL FINANCIAL INC 347,304 1,462,000 0.33%
38 DEERE & CO 332,399 1,399,000 0.32%
39 FMR LLC 325,000 1,368,000 0.31%
40 LOS ANGELES CAPITAL MANAGEMENT LLC 321,710 1,354,000 0.31%
41 MILLENNIUM MANAGEMENT LLC 302,147 1,272,000 0.29%
42 GOLDMAN SACHS GROUP INC 301,688 1,270,000 0.29%
43 TEACHERS ADVISORS, LLC 286,447 1,206,000 0.27%
44 VILLERE ST DENIS J & CO LLC 284,186 1,196,000 0.27%
45 State of New Jersey Common Pension Fund A 275,000 1,158,000 0.26%
46 NEW YORK STATE COMMON RETIREMENT FUND 272,165 1,146,000 0.26%
47 AQR CAPITAL MANAGEMENT LLC 268,800 1,132,000 0.26%
48 TWO SIGMA INVESTMENTS, LP 262,462 1,104,000 0.25%
49 CITIGROUP INC 262,124 1,104,000 0.25%
50 PUBLIC SECTOR PENSION INVESTMENT BOARD 257,658 1,085,000 0.25%
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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.