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

Institutional Holders (2014Q4)
Portfolio Summary: 148 Institutional holders with a total value of $280,481,973.
#
Manager Name
Shares
Value ($)
%
Options
Notes
1 Invesco Ltd. 31,797,788 87,444,000 31.18%
2 VANGUARD GROUP INC 8,491,811 23,353,000 8.33%
3 BlackRock Fund Advisors 7,592,761 20,880,000 7.44%
4 WELLS FARGO & COMPANY/MN 6,074,495 16,705,000 5.96%
5 DIMENSIONAL FUND ADVISORS LP 4,710,949 12,955,000 4.62%
6 BlackRock Institutional Trust Company, N.A. 3,715,238 10,217,000 3.64%
7 STATE STREET CORP 2,969,428 8,166,000 2.91%
8 Neuberger Berman Group LLC 2,766,992 7,609,000 2.71%
9 PUTNAM INVESTMENTS LLC 2,536,489 6,975,000 2.49%
10 AMERIPRISE FINANCIAL INC 2,262,403 6,221,000 2.22%
11 NORGES BANK 2,089,592 5,747,000 2.05%
12 JPMORGAN CHASE & CO 1,915,448 5,267,000 1.88%
13 Bank of New York Mellon Corp 1,515,232 4,167,000 1.49%
14 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 1,513,924 4,164,000 1.48%
15 NORTHERN TRUST CORP 1,475,484 4,058,000 1.45%
16 AMERICAN CENTURY COMPANIES INC 1,083,420 2,979,000 1.06%
17 ROYCE & ASSOCIATES LP 1,078,200 2,965,000 1.06%
18 TIAA CREF INVESTMENT MANAGEMENT LLC 950,765 2,615,000 0.93%
19 PANAGORA ASSET MANAGEMENT INC 919,365 2,528,000 0.90%
20 PRINCIPAL FINANCIAL GROUP INC 809,157 2,225,000 0.79%
21 GEODE CAPITAL MANAGEMENT, LLC 792,043 2,178,000 0.78%
22 SUSQUEHANNA INTERNATIONAL GROUP, LLP 746,359 2,052,000 0.73%
23 OXFORD ASSET MANAGEMENT LLP 665,712 1,839,000 0.66%
24 RENAISSANCE TECHNOLOGIES LLC 655,800 1,803,000 0.64%
25 GOLDMAN SACHS GROUP INC 651,888 1,793,000 0.64%
26 DEUTSCHE BANK AG\ 627,718 1,725,000 0.62%
27 Counsel Portfolio Services Inc. 577,175 1,587,000 0.57%
28 GUGGENHEIM CAPITAL LLC 551,668 1,517,000 0.54%
29 CALIFORNIA PUBLIC EMPLOYEES RETIREMENT SYSTEM 558,300 1,368,000 0.49%
30 BlackRock Investment Management, LLC 469,869 1,292,000 0.46%
31 PARAMETRIC PORTFOLIO ASSOCIATES LLC 418,968 1,152,000 0.41%
32 NEW YORK STATE TEACHERS RETIREMENT SYSTEM 415,082 1,141,000 0.41%
33 BOGLE INVESTMENT MANAGEMENT L P /DE/ 407,451 1,120,000 0.40%
34 PRUDENTIAL FINANCIAL INC 366,304 1,007,000 0.36%
35 State of New Jersey Common Pension Fund D 310,000 853,000 0.30%
36 Nationwide Fund Advisors 290,722 799,000 0.28%
37 BRIDGEWAY CAPITAL MANAGEMENT, LLC 290,000 798,000 0.28%
38 DEERE & CO 287,031 789,000 0.28%
39 TEACHERS ADVISORS, LLC 264,198 727,000 0.26%
40 MENTA CAPITAL LLC 260,788 717,000 0.26%
41 NEW YORK STATE COMMON RETIREMENT FUND 255,965 704,000 0.25%
42 COMERICA BANK 249,800 686,000 0.24%
43 PUBLIC SECTOR PENSION INVESTMENT BOARD 241,449 664,000 0.24%
44 CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 239,590 659,000 0.23%
45 STRS OHIO 210,400 579,000 0.21%
46 ALLIANCEBERNSTEIN L.P. 202,000 556,000 0.20%
47 WELLINGTON MANAGEMENT GROUP LLP 198,356 546,000 0.19%
48 RHUMBLINE ADVISERS 194,431 535,000 0.19%
49 LUCUS ADVISORS LLC 183,633 505,000 0.18%
50 CREDIT SUISSE AG/ 158,610 437,000 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.