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

Institutional Holders (2015Q4)
Portfolio Summary: 82 Institutional holders with a total value of $42,414,729.
#
Manager Name
Shares
Value ($)
%
Options
Notes
1 Invesco Ltd. 28,426,585 14,299,000 33.71%
2 Counsel Portfolio Services Inc. 791,037 5,970,000 14.08%
3 VANGUARD GROUP INC 6,291,508 3,165,000 7.46%
4 DIMENSIONAL FUND ADVISORS LP 4,193,744 2,110,000 4.97%
5 WELLS FARGO & COMPANY/MN 4,093,596 2,059,000 4.85%
6 BlackRock Fund Advisors 3,699,455 1,861,000 4.39%
7 BlackRock Institutional Trust Company, N.A. 3,418,216 1,720,000 4.06%
8 Neuberger Berman Group LLC 2,962,701 1,491,000 3.52%
9 RENAISSANCE TECHNOLOGIES LLC 2,612,500 1,314,000 3.10%
10 NORGES BANK 1,983,679 998,000 2.35%
11 GOLDMAN SACHS GROUP INC 1,871,766 942,000 2.22%
12 NORTHERN TRUST CORP 1,506,333 758,000 1.79%
13 ROYCE & ASSOCIATES LP 1,078,200 542,000 1.28%
14 JACOBS LEVY EQUITY MANAGEMENT, INC 861,163 433,000 1.02%
15 TIAA CREF INVESTMENT MANAGEMENT LLC 856,322 431,000 1.02%
16 MILLENNIUM MANAGEMENT LLC 837,986 422,000 0.99%
17 GEODE CAPITAL MANAGEMENT, LLC 764,960 384,000 0.91%
18 Bank of New York Mellon Corp 674,581 341,000 0.80%
19 CALIFORNIA PUBLIC EMPLOYEES RETIREMENT SYSTEM 601,900 303,000 0.71%
20 BlackRock Investment Management, LLC 507,388 255,000 0.60%
21 PARAMETRIC PORTFOLIO ASSOCIATES LLC 459,342 231,000 0.54%
22 BRIDGEWAY CAPITAL MANAGEMENT, LLC 360,010 181,000 0.43%
23 State of New Jersey Common Pension Fund D 310,000 156,000 0.37%
24 TWO SIGMA INVESTMENTS, LP 288,955 145,000 0.34%
25 CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 261,518 132,000 0.31%
26 STRS OHIO 220,800 111,000 0.26%
27 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 220,300 111,000 0.26%
28 RHUMBLINE ADVISERS 207,244 104,000 0.25%
29 TEACHERS ADVISORS, LLC 207,426 104,000 0.25%
30 HighTower Advisors, LLC 200,313 101,000 0.24%
31 Nationwide Fund Advisors 194,245 98,000 0.23%
32 CITADEL ADVISORS LLC 176,104 89,000 0.21%
33 CREDIT SUISSE AG/ 165,313 84,000 0.20%
34 RUSSELL FRANK CO/ 149,409 74,000 0.17%
35 ALLIANCEBERNSTEIN L.P. 189,250 74,000 0.17%
36 NEW YORK STATE COMMON RETIREMENT FUND 129,200 65,000 0.15%
37 TWO SIGMA ADVISERS, LP 124,668 63,000 0.15%
38 LOS ANGELES CAPITAL MANAGEMENT LLC 123,100 62,000 0.15%
39 Virtu KCG Holdings LLC 118,050 59,000 0.14%
40 STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM 112,084 56,000 0.13%
41 UBS Group AG 107,859 55,000 0.13%
42 VOYA INVESTMENT MANAGEMENT LLC 84,580 43,000 0.10%
43 AMERICAN INTERNATIONAL GROUP, INC. 82,640 42,000 0.10%
44 AQR CAPITAL MANAGEMENT LLC 69,064 35,000 0.08%
45 Connor, Clark & Lunn Investment Management Ltd. 65,450 33,000 0.08%
46 BLACKROCK ADVISORS LLC 58,377 29,000 0.07%
47 DRIEHAUS CAPITAL MANAGEMENT LLC 55,245 28,000 0.07%
48 CITIGROUP INC 43,625 22,000 0.05%
49 STOKES & HUBBELL CAPITAL MANAGEMENT, LLC 38,607 19,000 0.04%
50 DEUTSCHE BANK AG\ 34,767 16,000 0.04%
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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.