| Chevron Corporation |
13,634 |
| BP British Petroleum |
3,585 |
| Exxon Mobil Corporation |
3,194 |
| Shell Oil Company |
3,011 |
| ConocoPhillips Company |
2,052 |
| Baker Hughes Incorporated |
1,400 |
| Anadarko Petroleum Corporation |
1,131 |
| Fluor Corporation |
1,125 |
| Marathon Oil Corporation |
969 |
| Valero Energy Corporation |
902 |
| National Oilwell Varco |
744 |
| Occidental Petroleum Corporation |
736 |
| EnCana Corporation |
718 |
| Hess Corporation |
671 |
| Weatherford International Ltd. |
577 |
| Apache Corporation |
561 |
| Sunoco, Inc. |
499 |
| Enbridge Inc. |
473 |
| Chesapeake Energy Corporation |
464 |
| Alberta Research Council |
463 |
| Tesoro Corporation |
439 |
| Atmos Energy Corporation |
434 |
| Petro-Canada |
423 |
| ONEOK, Inc. |
416 |
| BJ Services Company |
407 |
| CITGO Petroleum Corporation |
395 |
| BG Group plc |
379 |
| Chevron Phillips Chemical Company LP |
358 |
| EOG Resources, Inc. |
343 |
| Murphy Oil Corporation |
341 |
| Pioneer Natural Resources Company |
332 |
| Marathon Petroleum Company |
279 |
| Husky Energy Inc. |
273 |
| Aera Energy LLC |
271 |
| Enterprise Products Partners L.P |
268 |
| Transocean Inc. |
267 |
| The Lincoln Electric Company |
262 |
| Newfield Exploration Company |
250 |
| XTO Energy Inc. |
247 |
| Western Refining, Inc. |
241 |
| Suncor Energy Inc. |
237 |
| Oceaneering International, Inc. |
236 |
| Southwestern Energy Company |
227 |
| Marathon Ashland Petroleum LLC |
226 |
| Hydro Aluminum North America |
224 |
| M-I SWACO |
222 |
| Flint Hills Resources, LP |
220 |
| CGGVeritas |
218 |
| Speedway SuperAmerica, LLC |
214 |
| Talisman Energy Inc. |
211 |
| Imperial Oil Ltd |
185 |
| Champion Technologies, Inc. |
183 |
| Plains All American Pipeline, L.P. |
183 |
| SemGroup LP |
183 |
| NATCO Group Inc. |
180 |
| National Fuel Gas Company |
179 |
| Energen Corporation |
177 |
| McDermott International, Inc. |
169 |
| Canadian Natural Resources Limited |
160 |
| SynCrude Canada Limite |
159 |
| Forest Oil Corporation |
148 |
| RaceTrac Petroleum, Inc. |
144 |
| Flying J Inc. |
140 |
| ION Geophysical Corporation |
139 |
| Reliance Industries Limited |
135 |
| StatoilHydro |
125 |
| TEPPCO Partners, L.P. |
125 |
| Greene, Tweed |
123 |
| Hunt Oil Company |
120 |
| Gilbarco Veeder-Root |
118 |
| Hilcorp Energy Company |
116 |
| Black Hills Energy |
115 |
| Holly Corporation |
114 |
| Swift Energy Company |
112 |
| Aramco Services Company |
110 |
| Lufkin Industries, Inc. |
104 |
| NuStar Energy L.P. |
103 |
| Cabot Oil & Gas Corporation |
103 |
| Netherland, Sewell |
101 |
| Turner Industries Group, L.L.C. |
100 |
| Buckeye Partners, L.P. |
100 |
| World Fuel Services Corporation |
97 |
| SunOpta Inc. |
97 |
| Black Hills Corp. |
97 |
| Sinclair Oil Corporation |
96 |
| Expro North Sea Ltd |
94 |
| International Power |
88 |
| Harbert Management Corp |
87 |
| Repsol YPF |
85 |
| Alyeska Pipeline |
84 |
| Inergy, L.P. |
84 |
| Cimarex Energy Co. |
84 |
| Vopak Terminals North America Inc |
84 |
| The Panhandle Pipe Line Company |
83 |
| Avfuel Corporation |
80 |
| Georgia Gulf Corporation |
73 |
| Whiting Petroleum Corporation |
72 |
| DCP Midstream |
72 |
| Frontier Oil Corporation |
71 |
| EnerMark Inc. |
70 |
| Alliance Pipeline Inc. |
68 |
| Copano Energy LLC |
67 |
| Stone Energy Corporation |
62 |
| Cudd Pressure Control, Inc. (US Headquarters) |
62 |
| CVR Energy, Inc. |
61 |
| EXCO Resources, Inc. |
61 |
| Sprague Energy |
61 |
| Boardwalk Pipeline Partners, LP |
61 |
| Berry Petroleum Company |
59 |
| Zetec |
58 |
| Pengrowth Corporation |
57 |
| Diamond Offshore Drilling, Inc. |
57 |
| Hercules Offshore, Inc. |
57 |
| Shell Trading (US) Company |
57 |
| Energy Partners, Ltd. |
56 |
| Petro-Hunt, L.L.C. |
56 |
| U.S. Oil Co., Inc. |
55 |
| Vetco Gray Inc |
55 |
| St. Mary Land & Exploration Company |
55 |
| Nerac, Inc. |
54 |
| Basic Energy Services, Inc. |
54 |
| Shell Canada Limited |
53 |
| RPC, Inc. |
53 |
| ineos |
52 |
| Bosselman, Inc. |
51 |
| Williston Basin Interstate Pipeline Company |
49 |
| United Refining Company |
49 |
| Vitol S.A., Inc. |
49 |
| ATP Oil & Gas Corporation |
48 |
| Citation Oil & Gas Corp. |
48 |
| Logan Oil Tools, Inc. |
48 |
| Rosetta Resources |
47 |
| Kern River Gas Transmission Co. |
46 |
| Petroleum Geo-Services |
46 |
| Gate Petroleum Company |
46 |
| Doyon, Limited |
45 |
| Penn Virginia Corporation |
45 |
| True Companies |
45 |
| TransMontaigne Inc. |
45 |
| Paramount Petroleum Corporation |
45 |
| Clean Energy |
45 |
| Walchandnagar Industries |
44 |
| ALON USA |
43 |
| ING Lease (UK) Limited |
43 |
| Chemoil Corporation |
42 |
| New Tech Engineering |
42 |
| Castle Oil Corporation |
41 |
| Enventure Global Technology |
41 |
| Ultramar |
41 |
| CENTENNIAL COAL COMPANY LIMITED |
41 |
| Tauber Oil Company |
40 |
| Bergelectric Corporation |
39 |
| Premier Oil |
39 |
| MTC |
38 |
| Atwood Oceanics, Inc. |
38 |
| EV Energy Partners, L.P. |
38 |
| Southern Star Central Gas Pipeline, Inc |
38 |
| Hunt Refining |
37 |
| Frontier Drilling |
37 |
| Manti Resources |
36 |
| European Metal Recycling Limited |
36 |
| Gulf Oil Limited Partnership |
35 |
| Kaiser-Francis Oil Co. |
35 |
| Modec International LLC |
35 |
| DeGolyer and MacNaughton |
33 |
| Colonial Group Inc. |
33 |
| Crown Central Petroleum Corporation |
33 |
| Texon LP |
33 |
| Eagle Rock Energy Partners, L.P. |
33 |
| PFC Energy |
33 |
| ARC Energy Trust |
32 |
| Venoco, Inc. |
32 |
| Stallion Oilfield Services |
32 |
| Patterson-UTI Energy, Inc. |
31 |
| Petroleum Development Corporation |
30 |
| PDV America, Inc. |
30 |
| Atco Midstream |
30 |
| HighMount Exploration |
30 |
| Mansfield Oil Company |
29 |
| Rineco Chemical Industries |
29 |
| PetroQuest Energy, Inc. |
29 |
| Wink, Inc. |
29 |
| Advanced Resources Intl |
29 |
| Great Lakes Gas Transmission Company |
29 |
| Apex Oil Company, Inc. |
29 |
| IMV Projects |
29 |
| The Sprint Companies |
29 |
| Advantage Oil & Gas Ltd |
29 |
| BreitBurn Energy Partners L.P. |
28 |
| MFA Oil Company |
28 |
| Energy XXI |
28 |
| Gibson Energy Ltd. |
28 |
| Bottini Propane Inc. d/b/a Bottini Fuel |
28 |
| American Refining Group Inc |
27 |
| Tetco Incorporated |
27 |
| Hiland Partners LP |
27 |
| Center Oil Company |
26 |
| National Fuel Resources, Inc. |
26 |
| Mobile Gas |
26 |
| Whitaker Oil Company, Inc. |
26 |
