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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)
Portfolio Summary: 4,548 holdings with a total value of $7,083,142,000.
#
Name
Shares
Value ($)
%
Options
Notes
4451 SKY-MOBI LTD 500 1,000 0.00% Call
4452 CONCERT PHARMACEUTICALS INC 100 1,000 0.00% Put
4453 RESEARCH FRONTIERS INC 218 1,000 0.00%
4454 PFENEX INC COM 100 1,000 0.00%
4455 LSB INDS INC 100 1,000 0.00% Put
4456 SCORPIO TANKERS INC 200 1,000 0.00% Call
4457 GSV CAP CORP 200 1,000 0.00% Put
4458 PHOTOMEDEX INC COM PAR $0.01 1,400 1,000 0.00%
4459 AGENUS INC 200 1,000 0.00% Put
4460 MOMENTA PHARMACEUTICALS INC 78 1,000 0.00%
4461 QUINSTREET INC COM USD0.001 400 1,000 0.00%
4462 INTERNAP CORP 400 1,000 0.00% Call
4463 ASHFORD HOSPITALITY TR INC COM SHS 88 1,000 0.00%
4464 ARATANA THERAPEUTICS INC 200 1,000 0.00% Put
4465 INFOBLOX INC 42 1,000 0.00%
4466 TRUECAR INC 200 1,000 0.00% Put
4467 TETRALOGIC PHARMA CO 3,000 1,000 0.00%
4468 CHINA AUTOMOTIVE SYS INC 140 1,000 0.00%
4469 COMSTOCK RES INC 1,000 1,000 0.00% Put
4470 ENERGOUS CORP 100 1,000 0.00% Put
4471 BONANZA CREEK ENERGY INC 600 1,000 0.00% Call
4472 Mercer International 142 1,000 0.00%
4473 CLOUD PEAK ENERGY INC 500 1,000 0.00% Put
4474 SERVICESOURCE INTL INC 200 1,000 0.00% Call
4475 REVOLUTION LIGHTING TECHNOLOGI COM NEW 96 1,000 0.00%
4476 DERMA SCIENCES ORD 209 1,000 0.00%
4477 IXYS CORP 100 1,000 0.00% Put
4478 TRINITY BIOTECH PLC 100 1,000 0.00%
4479 SPECTRUM PHARMACEUTICALS INC 200 1,000 0.00% Put
4480 CALAMOS ASSET MANAGEMENT CL A ORD 86 1,000 0.00%
4481 ENERPLUS CORP 300 1,000 0.00% Put
4482 OREXIGEN THERAPEUTICS INC 1,900 1,000 0.00% Put
4483 DELCATH SYS INC COM NEW 5,123 1,000 0.00%
4484 UNIQURE NV 100 1,000 0.00% Call
4485 AMBEV SA 200 1,000 0.00% Call
4486 BARRETT BILL CORP 200 1,000 0.00% Put
4487 UNITED DEV FDG IV 200 1,000 0.00% Put
4488 KAPSTONE PAPER & PACKAGING C 100 1,000 0.00% Call
4489 GERDAU S A 500 1,000 0.00% Put
4490 MICROVISION INC DEL 600 1,000 0.00% Put
4491 OPOWER INC 100 1,000 0.00% Call
4492 APPROACH RESOURCES INC 900 1,000 0.00% Call
4493 DORCHESTER MINERALS LP 100 1,000 0.00% Call
4494 ENTEROMEDICS INC 1,328 1,000 0.00%
4495 CATALYST BIOSCIENCES INC 300 1,000 0.00% Call
4496 POLYCOM INC 102 1,000 0.00%
4497 ELEVEN BIOTHERAPEUTICS INC 2,400 1,000 0.00%
4498 AGILYSYS INC COM 100 1,000 0.00%
4499 HARVEST NATURAL RESOURCES IN 1,652 1,000 0.00%
4500 TIVO INC 100 1,000 0.00% Put
Page 90 of 91

Portfolio data is normalized using SEC Form 13F filings, including the Original 13F-HR (0000932540-16-000021, filed 2016.05.12).

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.