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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
151 AK STL HLDG CORP 2,231,000 9,214 0.13% Call
152 AKAMAI TECHNOLOGIES INC 1,300 72 0.00% Put
153 AKAMAI TECHNOLOGIES INC 3,800 211 0.00% Call
154 AKEBIA THERAPEUTICS INC 51,800 467 0.01% Put
155 AKEBIA THERAPEUTICS INC 36,400 328 0.00% Call
156 AKEBIA THERAPEUTICS INC COM 17,276 156 0.00%
157 AKORN INC 46,800 1,101 0.02% Put
158 AKORN INC 67,800 1,595 0.02% Call
159 AKORN INC 8,485 200 0.00%
160 ALAMOS GOLD INC NEW 115,100 609 0.01% Put
161 ALAMOS GOLD INC NEW 295,300 1,562 0.02% Call
162 ALARM COM HLDGS INC 200 5 0.00% Call
163 ALASKA AIR GROUP INC 11,300 927 0.01% Put
164 ALASKA AIR GROUP INC 16,000 1,312 0.02% Call
165 ALASKA COMMUNICATIONS SYS GR 10,900 19 0.00% Put
166 ALASKA COMMUNICATIONS SYS GR 11,100 20 0.00% Call
167 ALBANY MOLECULAR RESH INC 8,300 127 0.00% Call
168 ALBANY MOLECULAR RESH INC 61,900 946 0.01% Put
169 ALBANY MOLECULAR RESH INC 31,141 476 0.01%
170 ALBEMARLE CORP 47,400 3,030 0.04% Put
171 ALBEMARLE CORP 42,500 2,717 0.04% Call
172 ALCOA INC 2,292,500 21,962 0.31% Put
173 ALCOA INC 595,400 5,704 0.08% Call
174 ALCOBRA LTD 199,031 754 0.01%
175 ALCOBRA LTD 14,700 56 0.00% Call
176 ALCOBRA LTD 10,300 39 0.00% Put
177 ALDER BIOPHARMACEUTICALS INC 1,200 29 0.00% Call
178 ALDER BIOPHARMACEUTICALS INC 3,700 91 0.00% Put
179 ALERE INC 38,800 1,964 0.03% Put
180 ALERE INC 11,700 592 0.01% Call
181 ALERE INC 6,096 309 0.00%
182 ALEXCO RESOURCE CORP 120,000 116 0.00% Call
183 ALEXCO RESOURCE CORP 122 0 0.00%
184 ALEXZA PHARMACEUTICALS INC 48,300 23 0.00% Call
185 ALIBABA GROUP HLDG LTD 104,800 8,282 0.12% Put
186 ALIBABA GROUP HLDG LTD 44,527 3,519 0.05%
187 ALIBABA GROUP HLDG LTD 236,700 18,706 0.26% Call
188 ALIGN TECHNOLOGY INC 1,000 73 0.00% Call
189 ALIGN TECHNOLOGY INC 32,700 2,377 0.03% Put
190 ALIMERA SCIENCES INC 1,306 2 0.00%
191 ALKERMES PLC 10,100 345 0.00% Put
192 ALKERMES PLC 9,000 308 0.00% Call
193 ALKERMES PLC 871 30 0.00%
194 ALLEGHENY TECHNOLOGIES INC 9,900 161 0.00% Put
195 ALLEGHENY TECHNOLOGIES INC 50,400 822 0.01% Call
196 ALLERGAN PLC 529,200 141,841 2.00% Put
197 ALLERGAN PLC 161,093 43,178 0.61%
198 ALLERGAN PLC 239,100 64,086 0.90% Call
199 ALLIANCE FIBER OPTIC PRODS I 2,600 38 0.00% Put
200 ALLIANCE FIBER OPTIC PRODS I 10,100 149 0.00% Call
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