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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
351 APPLIED MICRO CIRCUITS CORP 85,100 550 0.01% Put
352 APPLIED MICRO CIRCUITS CORP 2,600 17 0.00% Call
353 APPLIED MICRO CIRCUITS ORD 51,928 335 0.00%
354 APPLIED OPTOELECTRONICS INC 1,800 27 0.00% Call
355 APPROACH RESOURCES INC 75,700 88 0.00% Put
356 APRICUS BIOSCIENCES INC 4,400 3 0.00% Put
357 APRICUS BIOSCIENCES INC 66,700 39 0.00% Call
358 ARALEZ PHARMACEUTICALS INC 46,700 166 0.00% Put
359 ARALEZ PHARMACEUTICALS INC 24,200 86 0.00% Call
360 ARALEZ PHARMACEUTICALS INC 32,963 117 0.00%
361 ARAMARK 500 17 0.00% Put
362 ARAMARK 12,600 417 0.01% Call
363 ARATANA THERAPEUTICS INC 700 4 0.00%
364 ARATANA THERAPEUTICS INC 200 1 0.00% Put
365 ARBUTUS BIOPHARMA CORP 12,800 53 0.00% Call
366 ARBUTUS BIOPHARMA CORP 16,000 66 0.00% Put
367 ARBUTUS BIOPHARMA CORP 17,456 72 0.00%
368 ARCELORMITTAL SA LUXEMBOURG 275,500 1,262 0.02% Call
369 ARCELORMITTAL SA LUXEMBOURG 199,400 913 0.01% Put
370 ARCHROCK INC 100 1 0.00% Put
371 ARCOS DORADOS HOLDINGS INC 26,200 98 0.00% Call
372 ARCOS DORADOS HOLDINGS INC 7,500 28 0.00% Put
373 ARCTIC CAT INC 21,000 353 0.00% Put
374 ARCTIC CAT INC 1,100 18 0.00% Call
375 ARCTIC CAT INC COM 4,127 69 0.00%
376 ARENA PHARMACEUTICALS INC 190,200 375 0.01% Put
377 ARENA PHARMACEUTICALS INC 295,400 582 0.01% Call
378 ARENA PHARMACEUTICALS INC 625,368 1,232 0.02%
379 ARES CAP CORP 1,000 15 0.00% Put
380 ARES CAP CORP 3,500 52 0.00% Call
381 ARES CAPITAL CORP 750 11 0.00%
382 ARES MGMT L P 4,600 71 0.00% Call
383 ARIAD PHARMACEUTICALS INC 68,900 440 0.01% Put
384 ARIAD PHARMACEUTICALS INC 346,100 2,212 0.03% Call
385 ARIAD PHARMACEUTICALS ORD (NMS) 48,395 309 0.00%
386 ARISTA NETWORKS INC 34,800 2,196 0.03% Put
387 ARISTA NETWORKS INC 6,459 408 0.01%
388 ARISTA NETWORKS INC 200 13 0.00% Call
389 ARM HLDGS PLC 700 31 0.00% Put
390 ARM HLDGS PLC 24,600 1,075 0.02% Call
391 ARMOUR RESIDENTIAL REIT INC 97,000 2,088 0.03% Put
392 ARMOUR RESIDENTIAL REIT INC 12,600 271 0.00% Call
393 ARMOUR RESIDENTIAL REIT INC 16,686 359 0.01%
394 ARMSTRONG WORLD INDS INC NEW 1,200 58 0.00% Put
395 ARMSTRONG WORLD INDS INC NEW COM 1,200 58 0.00%
396 AROTECH CORP 5,500 13 0.00% Call
397 ARQULE INC 13,400 21 0.00% Call
398 ARRAY BIOPHARMA INC 151,800 448 0.01% Put
399 ARRIS INTL INC 58,300 1,336 0.02% Call
400 ARRIS INTL INC 3,097 71 0.00%
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