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

Institutional Holders (2015Q3)
Portfolio Summary: 120 Institutional holders with a total value of $35,753,537.
#
Manager Name
Shares
Value ($)
%
Options
Notes
1 Invesco Ltd. 31,804,811 12,403,000 34.69%
2 BlackRock Fund Advisors 8,311,582 3,242,000 9.07%
3 VANGUARD GROUP INC 5,307,957 2,070,000 5.79%
4 WELLS FARGO & COMPANY/MN 4,336,829 1,692,000 4.73%
5 DIMENSIONAL FUND ADVISORS LP 4,313,567 1,682,000 4.70%
6 BlackRock Institutional Trust Company, N.A. 3,515,253 1,371,000 3.83%
7 Neuberger Berman Group LLC 3,327,767 1,298,000 3.63%
8 STATE STREET CORP 2,547,124 993,000 2.78%
9 RENAISSANCE TECHNOLOGIES LLC 2,526,400 985,000 2.75%
10 NORGES BANK 1,983,679 774,000 2.16%
11 NORTHERN TRUST CORP 1,575,213 614,000 1.72%
12 Bank of New York Mellon Corp 1,570,320 612,000 1.71%
13 PANAGORA ASSET MANAGEMENT INC 1,468,312 573,000 1.60%
14 MCKINLEY CAPITAL MANAGEMENT LLC 1,221,525 476,000 1.33%
15 ROYCE & ASSOCIATES LP 1,078,200 420,000 1.17%
16 TIAA CREF INVESTMENT MANAGEMENT LLC 1,057,735 413,000 1.16%
17 JPMORGAN CHASE & CO 909,258 355,000 0.99%
18 PRINCIPAL FINANCIAL GROUP INC 831,407 324,000 0.91%
19 Counsel Portfolio Services Inc. 791,037 309,000 0.86%
20 GEODE CAPITAL MANAGEMENT, LLC 765,034 298,000 0.83%
21 AMERIPRISE FINANCIAL INC 595,674 232,000 0.65%
22 BlackRock Investment Management, LLC 562,636 219,000 0.61%
23 Sterling Capital Management LLC 551,130 215,000 0.60%
24 GUGGENHEIM CAPITAL LLC 549,929 214,000 0.60%
25 CALIFORNIA PUBLIC EMPLOYEES RETIREMENT SYSTEM 498,400 194,000 0.54%
26 PARAMETRIC PORTFOLIO ASSOCIATES LLC 471,864 184,000 0.51%
27 NEW YORK STATE TEACHERS RETIREMENT SYSTEM 405,582 158,000 0.44%
28 DEUTSCHE BANK AG\ 373,128 144,000 0.40%
29 GSA CAPITAL PARTNERS LLP 364,133 142,000 0.40%
30 BRIDGEWAY CAPITAL MANAGEMENT, LLC 360,010 140,000 0.39%
31 AQR CAPITAL MANAGEMENT LLC 353,392 138,000 0.39%
32 OFI Advisors LLC 342,867 134,000 0.37%
33 CORNERSTONE CAPITAL MANAGEMENT HOLDINGS LLC. 331,900 129,000 0.36%
34 GOLDMAN SACHS GROUP INC 313,999 122,000 0.34%
35 State of New Jersey Common Pension Fund D 310,000 121,000 0.34%
36 TEACHERS ADVISORS, LLC 287,783 112,000 0.31%
37 PRUDENTIAL FINANCIAL INC 284,704 111,000 0.31%
38 CITADEL ADVISORS LLC 259,864 101,000 0.28%
39 CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 256,792 100,000 0.28%
40 SG Americas Securities, LLC 229,977 90,000 0.25%
41 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 220,300 86,000 0.24%
42 STRS OHIO 220,800 86,000 0.24%
43 RHUMBLINE ADVISERS 220,074 86,000 0.24%
44 CREDIT SUISSE AG/ 219,041 85,000 0.24%
45 Parkwood LLC 205,708 80,000 0.22%
46 HighTower Advisors, LLC 200,313 78,000 0.22%
47 WELLINGTON MANAGEMENT GROUP LLP 198,356 78,000 0.22%
48 ALLIANCEBERNSTEIN L.P. 198,290 77,000 0.22%
49 BlackRock Group LTD 191,803 75,000 0.21%
50 Swiss National Bank 144,600 56,000 0.16%
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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.