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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 (2014Q3)
Portfolio Summary: 5,124 holdings with a total value of $6,492,678,000.
#
Name
Shares
Value ($)
%
Options
Notes
1 BARCLAYS BK PLC 3,875,700 120,806,000 1.86% Put
2 MALLINCKRODT PUB LTD CO 1,228,900 110,785,000 1.71% Put
3 GOPRO INC 762,200 71,418,000 1.10% Put
4 AMERICAN AIRLS GROUP INC 1,925,238 68,307,000 1.05%
5 AMERICAN AIRLS GROUP INC 1,802,200 63,942,000 0.98% Put
6 ACTAVIS PLC 221,800 53,516,000 0.82% Put
7 GOPRO INC 570,000 53,409,000 0.82% Call
8 YPF SOCIEDAD ANONIMA 1,399,100 51,753,000 0.80% Put
9 BLACKBERRY LTD 5,171,900 51,409,000 0.79% Put
10 VERTEX PHARMACEUTICALS INC 432,900 48,619,000 0.75% Put
11 PENNEY J C INC 4,732,200 47,511,000 0.73% Put
12 MALLINCKRODT PUB LTD CO 525,400 47,365,000 0.73% Call
13 INTEROIL CORP 790,200 42,876,000 0.66% Put
14 BARCLAYS BK PLC 1,355,800 42,260,000 0.65% Call
15 TWITTER INC 782,600 40,367,000 0.62% Put
16 ACTAVIS PLC 157,400 37,977,000 0.58% Call
17 HERBALIFE LTD 817,600 35,770,000 0.55% Put
18 ASTRAZENECA PLC 499,200 35,663,000 0.55% Put
19 HERTZ GLOBAL HOLDINGS INC 1,375,000 34,911,000 0.54% Put
20 BLACKBERRY LTD 3,440,697 34,201,000 0.53%
21 KINDER MORGAN INC DEL 844,300 32,370,000 0.50% Put
22 MANNKIND CORP 5,257,000 31,069,000 0.48% Call
23 KINDER MORGAN INC DEL 806,300 30,914,000 0.48% Call
24 VALEANT PHARMACEUTICALS INTL PUT 232,500 30,504,000 0.47% Put
25 ALLERGAN INC 168,800 30,078,000 0.46% Put
26 ASTRAZENECA PLC 414,600 29,619,000 0.46% Call
27 SEARS HLDGS CORP PUT 1,089,900 27,498,000 0.42% Put
28 Astrazeneca Plc ADR F 348,446 24,893,000 0.38%
29 JAZZ PHARMACEUTICALS PLC 155,000 24,887,000 0.38% Put
30 Hertz Global Holdings, Inc. 979,758 24,876,000 0.38%
31 TWITTER INC 470,671 24,277,000 0.37%
32 DRESSER-RAND GROUP INC 277,900 22,860,000 0.35% Call
33 SEARS HLDGS CORP 901,100 22,735,000 0.35% Call
34 TIME WARNER CABLE INC 157,700 22,628,000 0.35% Put
35 ABBVIE INC 373,200 21,556,000 0.33% Call
36 HERBALIFE LTD 486,700 21,293,000 0.33% Call
37 VALEANT PHARMACEUTICALS INTL 162,200 21,281,000 0.33% Call
38 PERRIGO CO PLC 140,800 21,147,000 0.33% Put
39 BANCO SANTANDER SA 2,195,800 20,860,000 0.32% Put
40 NQ MOBILE INC 2,872,200 20,019,000 0.31% Call
41 SIRIUS XM HOLDINGS INC 5,518,123 19,258,000 0.30%
42 TIME WARNER CABLE INC 133,500 19,156,000 0.30% Call
43 SUNEDISON INC 1,002,400 18,925,000 0.29% Call
44 VODAFONE GROUP PLC NEW 567,600 18,668,000 0.29% Put
45 NOKIA CORP 2,186,600 18,499,000 0.28% Put
46 YPF SOCIEDAD ANONIMA SPON ADR CL D 494,330 18,285,000 0.28%
47 TESLA MTRS INC PUT 74,000 17,958,000 0.28% Put
48 SPRINT CORP 2,819,300 17,874,000 0.28% Put
49 AMTRUST FINL SVCS INC 446,600 17,784,000 0.27% Put
50 CURRENCYSHS JAPANESE YEN TR 198,800 17,653,000 0.27% Put
Page 1 of 103

Portfolio data is normalized using SEC Form 13F filings, including the Original 13F-HR (0000932540-14-000022, filed 2014.10.31).

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.