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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 (2016Q1)
Original 13F HR (0000932540-16-000021) filed in 2016.05.12
#
Name
Shares
Value ($)
%
Options
Notes
51 ACACIA RESH CORP 2,291 9 0.00%
52 ACADIA COMPANY COM 2,395 132 0.00%
53 ACADIA HEALTHCARE COMPANY IN 3,600 198 0.00% Put
54 ACADIA HEALTHCARE COMPANY IN 300 17 0.00% Call
55 ACADIA PHARMACEUTICALS INC 417,800 11,682 0.16% Put
56 ACADIA PHARMACEUTICALS INC 533,700 14,922 0.21% Call
57 ACCELERATE DIAGNOSTICS INC 30,400 437 0.01% Call
58 ACCELERATE DIAGNOSTICS INC 2,757 40 0.00%
59 ACCELERATE DIAGNOSTICS INC 18,400 264 0.00% Put
60 ACCELERON PHARMA INC 561 15 0.00%
61 ACCELERON PHARMA INC 1,700 45 0.00% Put
62 ACCURAY INC 3,200 19 0.00% Put
63 ACCURAY INC 8,200 47 0.00% Call
64 ACELRX PHARMACEUTICALS INC 13,100 40 0.00% Call
65 ACELRX PHARMACEUTICALS INC 1,000 3 0.00% Put
66 ACETO CORP 100 2 0.00% Put
67 ACHILLION PHARMACEUTICALS IN 62,900 486 0.01% Put
68 ACHILLION PHARMACEUTICALS IN 76,489 591 0.01%
69 ACHILLION PHARMACEUTICALS INC 123,600 954 0.01% Call
70 ACORDA THERAPEUTICS INC 32,100 849 0.01% Put
71 ACORDA THERAPEUTICS INC 100 3 0.00% Call
72 ACORDA THERAPEUTICS INC 14,393 381 0.01%
73 ACTINIUM PHARMACEUTICALS INC 945 2 0.00%
74 ACTINIUM PHARMACEUTICALS INC 37,000 74 0.00% Call
75 ACTIVISION BLIZZARD INC 63,500 2,149 0.03% Put
76 ACTIVISION BLIZZARD INC 30,700 1,039 0.01% Call
77 ACTIVISION BLIZZARD INC 67,597 2,287 0.03%
78 ACURA PHARMACEUTICALS INC 2,207 6 0.00%
79 ACURA PHARMACEUTICALS INC 5,000 14 0.00% Put
80 ACXIOM CORP 21,600 463 0.01% Call
81 ADAMIS PHARMACEUTICALS CORP 13,500 83 0.00% Call
82 ADCARE HEALTH SYSTEMS INC 12,174 28 0.00%
83 ADCARE HEALTH SYSTEMS INC 16,300 38 0.00% Put
84 ADECOAGRO S A 230 3 0.00%
85 ADEPTUS HEALTH INC 600 33 0.00% Put
86 ADTRAN INC 3,400 69 0.00% Put
87 ADTRAN INC 100 2 0.00% Call
88 ADTRAN INC COM 5,114 103 0.00%
89 ADURO BIOTECH INC 20,462 262 0.00%
90 ADURO BIOTECH INC 8,800 113 0.00% Put
91 ADURO BIOTECH INC 3,400 44 0.00% Call
92 ADVANCED ENERGY INDS 5,000 174 0.00% Call
93 ADVANCED MICRO DEVICES INC 5,245,100 14,949 0.21% Put
94 ADVANCED MICRO DEVICES INC 742,000 2,115 0.03% Call
95 ADVANTAGE OIL & GAS LTD 500 3 0.00% Call
96 AECOM 2,600 80 0.00% Call
97 AECOM 1,100 34 0.00% Put
98 AEGEAN MARINE PETROLEUM NETW 2,736 21 0.00%
99 AEGEAN MARINE PETROLEUM NETW 2,400 18 0.00% Put
100 AEGERION PHARMACEUTICALS INC 15,100 56 0.00% Call
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