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Institutional Investment Manager
GROUP ONE TRADING LLC
GROUP ONE TRADING LLC (CIK: 0000932540) incorporated in Delaware, located at 425 S Financial Place, Chicago, IL. Institutional holdings reported to the SEC.

Institutional Holdings (2015Q2)
Portfolio Summary: 4,849 holdings with a total value of $7,147,569,000.
#
Name
Shares
Value ($)
%
Options
Notes
1 ENERGY RECOVERY INC 100 0 0.00% Put
2 DEX MEDIA INC NEW 100 0 0.00% Call
3 STRATA SKIN SCIENCES INC COM 1 0 0.00%
4 MATTSON TECHNOLOGY INC 100 0 0.00% Put
5 TAL ED GROUP 1 0 0.00%
6 IMMUNOCELLULAR THERAPEUTICS 300 0 0.00% Put
7 IMPAC MTG HLDGS INC COM NEW 1 0 0.00%
8 FIVE STAR SENIOR LIVING INC 100 0 0.00% Put
9 NORTHERN DYNASTY MINERALS LTD COM 900 0 0.00%
10 VONAGE HLDGS CORP 100 0 0.00% Call
11 RIGEL PHARMACEUTICALS INC 100 0 0.00% Call
12 NORTH ATLANTIC DRILLING LTD 200 0 0.00% Call
13 SMART TECHNOLOGIES INC 1 0 0.00%
14 NEOGENOMICS INC 22 0 0.00%
15 UQM TECHNOLOGIES INC COM 261 0 0.00%
16 MARATHON OIL CORP 9 0 0.00%
17 OCEANEERING INTL INC 7 0 0.00%
18 URANIUM RES INC 300 0 0.00% Call
19 DRDGOLD LIMITED 100 0 0.00%
20 SAFE BULKERS INC 100 0 0.00% Put
21 SAMSON OIL & GAS LTD 100 0 0.00% Call
22 MARTIN MIDSTREAM PRTNRS L P 7 0 0.00%
23 ASSEMBLY BIOSCIENCES INC 1 0 0.00%
24 GREAT PANTHER SILVER LTD 59 0 0.00%
25 GENETIC TECHNOLOGIES LTD 100 0 0.00% Put
26 SUNGY MOBILE LTD 3 0 0.00%
27 TOWERSTREAM CORP 135 0 0.00%
28 HARVEST NATURAL RESOURCES IN 100 0 0.00% Put
29 ROYALE ENERGY INC 81 0 0.00%
30 NOVATEL WIRELESS INC 100 0 0.00% Put
31 KEY ENERGY SVCS INC 200 0 0.00% Put
32 TORONTO DOMINION BK ONT 1 0 0.00%
33 DRAGONWAVE INC 97 0 0.00%
34 PARAGON OFFSHORE PLC 200 0 0.00% Put
35 STR Holdings Inc 3 0 0.00%
36 GOLAR LNG PARTNERS LP 9 0 0.00%
37 PACIFIC BIOSCIENCES CALIF IN 22 0 0.00%
38 NYMOX PHARMACEUTICAL CORP 300 0 0.00% Call
39 BOINGO WIRELESS INC COM 1 0 0.00%
40 LOUISIANA PAC CORP 4 0 0.00%
41 NANOSPHERE INC 76 0 0.00%
42 ALEXCO RESOURCE CORP 22 0 0.00%
43 WARREN RES INC 400 0 0.00% Call
44 FX ENERGY INC 200 0 0.00% Call
45 SILICON GRAPHICS INTL CORP 100 1,000 0.00% Call
46 CERAGON NETWORKS LTD 711 1,000 0.00%
47 PFSWEB INC COM STK 100 1,000 0.00%
48 SEADRILL PARTNERS LLC 100 1,000 0.00% Call
49 CRAFT BREW ALLIANCE INC 100 1,000 0.00% Put
50 ULTRA CLEAN HLDGS INC 100 1,000 0.00%
Page 1 of 97

Portfolio data is normalized using SEC Form 13F filings, including the Original 13F-HR (0000932540-15-000009, filed 2015.08.11).

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.