| Chevron Corporation |
13,467 |
| BP British Petroleum |
3,602 |
| Exxon Mobil Corporation |
3,192 |
| Shell Oil Company |
3,097 |
| ConocoPhillips Company |
2,196 |
| Baker Hughes Incorporated |
1,420 |
| Fluor Corporation |
1,188 |
| Anadarko Petroleum Corporation |
1,126 |
| Marathon Oil Corporation |
946 |
| Valero Energy Corporation |
913 |
| EnCana Corporation |
736 |
| National Oilwell Varco |
715 |
| Occidental Petroleum Corporation |
706 |
| Weatherford International Ltd. |
582 |
| Hess Corporation |
575 |
| Apache Corporation |
543 |
| Sunoco, Inc. |
525 |
| Enbridge Inc. |
480 |
| Tesoro Corporation |
479 |
| Alberta Research Council |
465 |
| ONEOK, Inc. |
462 |
| Chesapeake Energy Corporation |
454 |
| Atmos Energy Corporation |
447 |
| BJ Services Company |
394 |
| CITGO Petroleum Corporation |
392 |
| BG Group plc |
381 |
| Chevron Phillips Chemical Company LP |
367 |
| Petro-Canada |
366 |
| Murphy Oil Corporation |
354 |
| EOG Resources, Inc. |
331 |
| Pioneer Natural Resources Company |
288 |
| Marathon Petroleum Company |
280 |
| Husky Energy Inc. |
278 |
| Transocean Inc. |
276 |
| Enterprise Products Partners L.P |
272 |
| Aera Energy LLC |
271 |
| Newfield Exploration Company |
260 |
| Western Refining, Inc. |
253 |
| Hydro Aluminum North America |
250 |
| XTO Energy Inc. |
243 |
| Southwestern Energy Company |
238 |
| Marathon Ashland Petroleum LLC |
230 |
| M-I SWACO |
227 |
| Flint Hills Resources, LP |
226 |
| Oceaneering International, Inc. |
224 |
| CGGVeritas |
223 |
| Speedway SuperAmerica, LLC |
218 |
| Suncor Energy Inc. |
214 |
| Plains All American Pipeline, L.P. |
195 |
| Energen Corporation |
190 |
| Champion Technologies, Inc. |
187 |
| NATCO Group Inc. |
187 |
| Imperial Oil Ltd |
185 |
| National Fuel Gas Company |
182 |
| SemGroup LP |
181 |
| McDermott International, Inc. |
180 |
| Talisman Energy Inc. |
176 |
| SynCrude Canada Limite |
172 |
| Canadian Natural Resources Limited |
159 |
| Reliance Industries Limited |
157 |
| Forest Oil Corporation |
148 |
| RaceTrac Petroleum, Inc. |
143 |
| ION Geophysical Corporation |
140 |
| Gilbarco Veeder-Root |
137 |
| Hunt Oil Company |
134 |
| Netherland, Sewell |
131 |
| TEPPCO Partners, L.P. |
130 |
| Flying J Inc. |
127 |
| Greene, Tweed |
126 |
| StatoilHydro |
123 |
| Aramco Services Company |
119 |
| Holly Corporation |
118 |
| Sinclair Oil Corporation |
115 |
| Lufkin Industries, Inc. |
115 |
| Buckeye Partners, L.P. |
111 |
| SunOpta Inc. |
109 |
| Hilcorp Energy Company |
109 |
| NuStar Energy L.P. |
107 |
| World Fuel Services Corporation |
104 |
| Swift Energy Company |
103 |
| Turner Industries Group, L.L.C. |
100 |
| Harbert Management Corp |
96 |
| Inergy, L.P. |
90 |
| Cabot Oil & Gas Corporation |
90 |
| International Power |
89 |
| Black Hills Corp. |
88 |
| Cimarex Energy Co. |
88 |
| Vopak Terminals North America Inc |
88 |
| The Panhandle Pipe Line Company |
87 |
| Repsol YPF |
86 |
| Alyeska Pipeline |
84 |
| Copano Energy LLC |
80 |
| United Refining Company |
80 |
| Avfuel Corporation |
80 |
| Whiting Petroleum Corporation |
79 |
| DCP Midstream |
79 |
| Frontier Oil Corporation |
77 |
| Alliance Pipeline Inc. |
77 |
| Vetco Gray Inc |
76 |
| Georgia Gulf Corporation |
76 |
| Stone Energy Corporation |
75 |
| CVR Energy, Inc. |
72 |
| Cudd Pressure Control, Inc. (US Headquarters) |
72 |
| Sprague Energy |
71 |
| Hercules Offshore, Inc. |
70 |
| Shell Trading (US) Company |
68 |
| EnerMark Inc. |
67 |
| Gate Petroleum Company |
64 |
| U.S. Oil Co., Inc. |
62 |
| Zetec |
62 |
| Advanced Resources Intl |
62 |
| Petro-Hunt, L.L.C. |
62 |
| Boardwalk Pipeline Partners, LP |
62 |
| Pengrowth Corporation |
61 |
| Nerac, Inc. |
61 |
| Berry Petroleum Company |
60 |
| EXCO Resources, Inc. |
60 |
| Basic Energy Services, Inc. |
60 |
| St. Mary Land & Exploration Company |
59 |
| Expro North Sea Ltd |
58 |
| RPC, Inc. |
56 |
| ineos |
56 |
| Diamond Offshore Drilling, Inc. |
55 |
| Bosselman, Inc. |
55 |
| Energy Partners, Ltd. |
52 |
| Doyon, Limited |
51 |
| Tauber Oil Company |
50 |
| Vitol S.A., Inc. |
50 |
| Clean Energy Fuels Corporation |
49 |
| ATP Oil & Gas Corporation |
48 |
| Penn Virginia Corporation |
48 |
| Bergelectric Corporation |
48 |
| Williston Basin Interstate Pipeline Company |
47 |
| TransMontaigne Inc. |
47 |
| Southern Star Central Gas Pipeline, Inc |
47 |
| Paramount Petroleum Corporation |
46 |
| Citation Oil & Gas Corp. |
46 |
| Chemoil Corporation |
45 |
| Enventure Global Technology |
45 |
| Kaiser-Francis Oil Co. |
45 |
| Petroleum Geo-Services |
45 |
| ALON USA |
44 |
| Kern River Gas Transmission Co. |
44 |
| Walchandnagar Industries |
44 |
| ING Lease (UK) Limited |
43 |
| Castle Oil Corporation |
42 |
| True Companies |
42 |
| New Tech Engineering |
42 |
| CENTENNIAL COAL COMPANY LIMITED |
42 |
| Logan Oil Tools, Inc. |
41 |
| MTC |
40 |
| Eagle Rock Energy Partners, L.P. |
40 |
| Tullow Oil plc |
40 |
| Rosetta Resources |
39 |
| Hiland Partners LP |
39 |
| EV Energy Partners, L.P. |
39 |
| Colonial Group Inc. |
38 |
| Atwood Oceanics, Inc. |
37 |
| Wink, Inc. |
36 |
| Ultramar |
36 |
| Whitaker Oil Company, Inc. |
36 |
| Manti Resources |
36 |
| Frontier Drilling |
36 |
| European Metal Recycling Limited |
36 |
| Gulf Oil Limited Partnership |
35 |
| Texon LP |
35 |
| OPE, Inc |
35 |
| Modec International LLC |
35 |
| DeGolyer and MacNaughton |
34 |
| Crown Central Petroleum Corporation |
34 |
| PDV America, Inc. |
34 |
| BreitBurn Energy Partners L.P. |
33 |
| ARC Energy Trust |
33 |
| National Fuel Resources, Inc. |
33 |
| Apex Oil Company, Inc. |
33 |
| PFC Energy |
33 |
| Midnight Oil Exploration Ltd. |
32 |
| Venoco, Inc. |
32 |
| Mansfield Oil Company |
31 |
| Compton Petroleum Corporation |
31 |
| Petroleum Development Corporation |
31 |
| Rig-Up Services, Inc. |
31 |
| BLUE TEE Corp. |
30 |
| Mobile Gas |
30 |
| Atco Midstream |
30 |
| Hunt Refining |
29 |
| PetroQuest Energy, Inc. |
29 |
| Tetco Incorporated |
29 |
| Complete Production Services, Inc. |
29 |
| IMV Projects |
29 |
| Bottini Propane Inc. d/b/a Bottini Fuel |
29 |
| Palmer Manufacturing Co Inc |
29 |
| HighMount Exploration |
29 |
| Advantage Oil & Gas Ltd |
29 |
| American Refining Group Inc |
28 |
| Great Lakes Gas Transmission Company |
28 |
| Premier Oil |
28 |
| Energy XXI |
28 |
| Gibson Energy Ltd. |
28 |
| The Sprint Companies |
28 |
