| Dougherty, H W | 100629 | Petaluma | 1 | 1 |
| Doyle Huber Associates | 100630 | Vernal | 0 | 0 |
| Dreiling & Sons Inc | 100632 | Victoria | 1 | 1 |
| Drillco Inc | 100633 | Centerville | 2 | 2 |
| Drillex, LLCActive | 100634 | Draper | 1 | 1 |
| Driscoll, P L | 100635 | Salt Lake City | 0 | 0 |
| Duckbill Gun Club | 100636 | — | 1 | 1 |
| Dudley & Associates, LLC | 100637 | Denver | 5 | 1 |
| Dugan Production Corp | 100638 | Farmington | 6 | 1 |
| Dugan, Thomas A | 100639 | — | 1 | 1 |
| Duke Energy Field Services | 100640 | Denver | 0 | 0 |
| Duke Energy Trans & Trade | 100641 | Tulsa | 0 | 0 |
| Duke, Charles L | 100642 | — | 1 | 1 |
| Duncan Energy CompanyUNCAN ENERGY COMPANY | 100643 | Denver | 5 | 1 |
| Duncan Oil Inc | 100644 | Denver | 0 | 0 |
| Duncan, Raymond T | 100645 | Denver | 13 | 2 |
| Duncan, Walter Oil Prop | 100646 | Denver | 6 | 2 |
| Dunlap, D D | 100647 | Long Beach | 1 | 1 |
| Dunn, E D | 100648 | — | 2 | 1 |
| Dunn, W C | 100649 | — | 1 | 1 |
| Dunne Equities Inc | 100650 | Wichita | 1 | 1 |
| Dyco Petroleum Corporation | 100651 | Tulsa | 5 | 2 |
| Dyer, J G | 100652 | — | 1 | 1 |
| Dynamic Industrials Inc | 100653 | — | 1 | 1 |
| E B Clark | 100654 | — | 3 | 1 |
| E L K Oil Company | 100655 | — | 1 | 1 |
| Eagle Gas Marketing | 100656 | Oklahoma City | 0 | 0 |
| Eagle Oil & Gas Co | 100657 | — | 2 | 1 |
| Eagleridge Operating, LLC | 100658 | Dallas | 3 | 1 |
| Earl Eastburn Investments | 100659 | Austin | 0 | 0 |
| Earth Resources Corp | 100661 | Boulder | 0 | 0 |
| East Resources Inc | 100662 | Broomfield | 0 | 0 |
| Eastern Idaho Develop Co | 100663 | — | 1 | 1 |
| Eastern Water Solutions, LLC | 100665 | Provo | 0 | 0 |
| Echo Park Resources, LLCActive | 105840 | Vernal | 0 | 0 |
| EDF Trading North America LLCActive | 100666 | Houston | 0 | 0 |
| EDP Resources LLC | 100667 | Park City | 0 | 0 |
| Edward Mike Davis | 100668 | Las Vegas | 0 | 0 |
| Edwards & Harding Petro Co | 100669 | Abingdon | 3 | 1 |
| Edwards Energy Corporation | 100670 | Denver | 0 | 0 |
| Edwards Petroleum Company | 100671 | Sandy | 0 | 0 |
| EEX Corporation | 100672 | Houston | 2 | 1 |
| EGO Resources Inc | 100673 | Vernal | 0 | 0 |
| Eighty-Eight Oil Company | 100674 | Casper | 0 | 0 |
| El Capitan Drilling Co | 100675 | — | 3 | 1 |
| El Dorado Refining Company | 100676 | Tulsa | 1 | 1 |
| El Paso E&P Company LP | 100678 | Houston | 0 | 0 |
| El Paso E&P Company, LP | 100677 | Houston | 56 | 2 |
| El Paso Field Operations | 100679 | Houston | 0 | 0 |
| El Paso Midstream GroupActive | 100680 | Houston | 0 | 0 |
| El Paso Midstream GroupActive | 100681 | Houston | 0 | 0 |
| El Paso Natural Gas Co | 100682 | El Paso | 15 | 8 |
| El Paso Prod Oil & Gas Co | 100683 | Houston | 25 | 2 |
| Eland Energy Inc | 100684 | Dallas | 0 | 0 |
| Eldorado Oil Company | 100685 | — | 1 | 1 |
| Elk Operating Services, LLCActive | 104372 | Denver | 832 | 1 |
| Elk Production LLC | 100687 | Denver | 11 | 2 |
| Elk Production LLC | 100688 | Denver | 0 | 0 |
| Elk Production LLC | 100689 | Denver | 0 | 0 |
| Elk Production Uintah LLC | 100686 | Denver | 9 | 1 |
| Elk Resources, Inc | 100690 | Denver | 0 | 0 |
| Elk Resources, Inc | 100691 | Houston | 0 | 0 |
| Elk Resources, LLC | 100692 | Denver | 2 | 1 |
| Elk Resources, LLC | 100693 | Denver | 0 | 0 |
| Elk Run Energy LLCActive | 105882 | Dallas | 0 | 0 |
| Elkhorn Exploration CoActive | 105093 | Lehi | 3 | 1 |
| Elkhorn Operating Co | 100694 | Tulsa | 0 | 0 |
| Elliott Inc | 100695 | Roswell | 1 | 1 |
| Ellis, A C | 100696 | — | 2 | 1 |
| Elm Ridge Exploration Company | 100697 | Dallas | 12 | 1 |
| Elm Ridge Resources Inc | 100698 | Dallas | 8 | 1 |
| Elmer, G C | 100699 | — | 3 | 2 |
| Embar Oil Co | 100700 | — | 1 | 1 |
| Embar-Big-Six Oil Cos | 100701 | — | 1 | 1 |
| Emerald Oil and Mining Co | 100702 | Snowbird | 0 | 0 |
| Emery Resource Holdings LLCActive | 100703 | Scottsdale | 3 | 2 |
| Emery Resources Utah, LLC | 105353 | Allen | 0 | 0 |
| Emil B Kucera | 100704 | — | 1 | 1 |
| Empire Drilling | 100705 | — | 1 | 1 |
| Empire Energy | 100706 | Los Angeles | 0 | 0 |
| Empire Gas & Fuel Company | 100707 | — | 1 | 1 |
| Empire Petroleum Co | 100708 | — | 1 | 1 |
| Encana Oil & Gas (USA), IncActive | 100709 | Denver | 36 | 4 |
| Encana Oil & Gas (USA), IncActive | 100710 | Moab | 0 | 0 |
| Encore Energy LLC | 100711 | Fruita | 0 | 0 |
| Encore Operating LP | 100712 | Ft Worth | 0 | 0 |
| Endrex Corporation | 100713 | — | 4 | 2 |
| Enduring Energy, LLC | 104322 | Lawrence | 5 | 2 |
| Enduring Resources, LLC | 100714 | Denver | 501 | 1 |
| Enercor | 100715 | Salt Lake City | 0 | 0 |
| Energetics Inc | 100716 | — | 1 | 1 |
| Energetics Operating Co | 100717 | Englewood | 4 | 2 |
| Energy Associates | 100718 | — | 1 | 1 |
| Energy Hunters | 100719 | Layton | 1 | 1 |
| Energy Management Services | 100720 | Denver | 0 | 0 |
| Energy of the Rockies | 100721 | Manti | 0 | 0 |
| Energy Partners Nominee Co | 100722 | Denver | 0 | 0 |
| Energy Reserves Group | 100723 | — | 3 | 2 |
| Energy Resources Inc | 100724 | — | 0 | 0 |
| Enerplus Resources (USA) Corp | 100725 | Denver | 0 | 0 |
| EnerQuest Operating, LLCActive | 100726 | Oklahoma City | 2 | 1 |
| Enertech Energy Inc | 100727 | Los Angeles | 0 | 0 |
| EnerVest Operating, LLC | 100728 | Houston | 168 | 2 |
| English Oil Co | 100729 | — | 1 | 1 |
| English, P B | 100730 | — | 3 | 1 |
| Enoch Smith & Sons Co | 100731 | — | 2 | 1 |
| Enogex Exploration Corp | 100732 | Oklahoma City | 1 | 1 |
| Enpro LLC | 100733 | Cottonwood Heights | 0 | 0 |
| Enron Oil & Gas Co | 100734 | Big Piney | 58 | 2 |
| Enron Oil & Gas Co | 100735 | Vernal | 0 | 0 |
| Enron Trans & Trading | 100736 | Houston | 0 | 0 |
| Enserch Exploration Inc | 100737 | Dallas | 0 | 0 |
| Enserch Exploration Inc | 100738 | Dallas | 0 | 0 |
| Enserch Exploration Inc | 100739 | Vernal | 0 | 0 |
| Enstar Corporation | 100740 | Houston | 1 | 1 |
| Enterprise Crued Oil LLC | 100741 | Oklahoma City | 0 | 0 |
| Enterprise Products Operating LP | 100742 | Seminole | 2 | 1 |
| Entrada Oil & Gas | 100743 | — | 0 | 0 |
| Entrada Petroleum Corp | 100744 | — | 1 | 1 |
| Enviro-Tech/Coconino | 100745 | Salt Lake City | 0 | 0 |
| Environmental Energy Innovations | 100746 | Roosevelt | 0 | 0 |
| Envirotech of Utah Inc | 100747 | Salt Lake City | 0 | 0 |
| EOG Resources, IncActive | 100749 | Vernal | 563 | 7 |
| EOG Y Resources Inc | 100750 | Artesia | 0 | 0 |
| Eott | 100751 | Houston | 0 | 0 |
| EP Energy E&P Company, LPActive | 100752 | Houston | 81 | 2 |
| EP Operating Company LP | 100753 | Midland | 31 | 4 |
| Epic Resources Inc | 100754 | Roosevelt | 0 | 0 |
| EPS Resources Corp | 100755 | Englewood | 4 | 1 |
| Equitable Resources Energy | 100756 | Houston | 32 | 3 |
| Equitable Resources Energy | 100757 | Billings | 0 | 0 |
| Equity Oil Company | 100758 | Cody | 0 | 0 |
| Equity Oil Company | 100759 | Cody | 0 | 0 |
| Equiva Trading Co | 100760 | Houston | 0 | 0 |
| ERG Operating Company Inc | 100761 | Baytown | 0 | 0 |
| ERHC/Bass American Petro | 100762 | Roosevelt | 0 | 0 |
| Erickson, Lynn | 100763 | — | 2 | 1 |
| Escalante Exploration | 100764 | — | 2 | 1 |
| Escalera Resources Co | 100765 | Denver | 0 | 0 |
| Essex Refining Company | 100766 | Houston | 0 | 0 |
| Estate of Thelma Simmons | 100767 | Salt Lake City | 2 | 1 |
| Eureka Oil Co | 100770 | — | 1 | 1 |
| Evergreen Energy, IncActive | 100771 | Portland | 1 | 1 |
| Evergreen Oil Corp | 100772 | — | 2 | 1 |
| Evergreen Operating Corp | 100773 | Denver | 3 | 2 |
| Evertson Oil Company Inc | 100774 | Kimball | 8 | 1 |
| Exit Inc | 100775 | — | 1 | 1 |
| Explor Energy | 100776 | Denver | 1 | 1 |
| Exxon Corporation | 100777 | Houston | 55 | 10 |
| Exxon Corporation | 100778 | Midland | 0 | 0 |
| Exxon Mobil Corporation | 100779 | Houston | 7 | 2 |
| Exxonmobil Oil Corp | 100780 | Houston | 0 | 0 |
| F & M Oil Company Inc | 100781 | Wichita | 0 | 0 |
| F L Energy | 100782 | Holladay | 19 | 3 |
| Fagin Exploration Company | 100783 | — | 0 | 0 |
| Fair Oil LTD | 100784 | Tyler | 1 | 1 |
| Fair, Ralph E Inc | 100785 | San Antonio | 1 | 1 |
| Falcon Creek Resources | 100786 | Tulsa | 6 | 1 |
| Falcon Energy LLCActive | 100787 | Fruita | 1 | 1 |
| Falcon Exploration, Inc | 100788 | Wichita | 1 | 1 |
| Falcon Seaboard Drl Co | 100789 | Tulsa | 1 | 1 |
| Fallgren & Weightman | 100790 | — | 2 | 1 |
| Fat Chance Oil & Gas LLC | 100792 | Sheridan | 3 | 1 |
| Federal Oil Co | 100794 | — | 1 | 1 |
| Feldman, D D | 100796 | — | 2 | 1 |
| Feldt & Maytag | 100797 | Colorado Springs | 1 | 1 |
| Fellows Energy LTD | 100798 | Price | 11 | 3 |
| Fellows Energy LTD | 100799 | Lafayette | 0 | 0 |
| Ferguson & Bosworth | 100800 | — | 2 | 1 |
| Ferguson Oil Co | 100801 | — | 1 | 1 |
| Ferrell Gas Inc | 100802 | Liberty | 0 | 0 |
| Ferrellgas LP | 100803 | Liberty | 0 | 0 |
| Ferrovanadium Corp | 100804 | — | 1 | 1 |
| Fidelity E&P Company | 100807 | Denver | 17 | 1 |
| Fidelity Exp & Prod Co | 100808 | Denver | 0 | 0 |
| Fiml Natural Resources LLC (FNR) | 100809 | Denver | 99 | 2 |
| Fiml Natural Resources LLC (FNR) | 100810 | Denver | 0 | 0 |
| Fina Oil & Chemical Co | 100811 | Oklahoma City | 2 | 1 |
| Findamental Oil Corp | 100868 | — | 4 | 1 |
| Finley | 100812 | — | 3 | 1 |
| Finley Resources, IncActive | 100813 | Fort Worth | 1,006 | 2 |
| First Energy Corporation | 100815 | — | 0 | 0 |
| First National Co of Marsh | 100822 | New Orleans | 0 | 0 |
| First Zone Production | 100825 | Salt Lake City | 16 | 1 |
| Five-Nines Resources, LLC | 105222 | Shreveport | 4 | 2 |
| Fix, Earl E | 100826 | — | 1 | 1 |
| Flader, Herman | 100827 | — | 1 | 1 |
| Flare Energy Corporation | 100828 | Denver | 2 | 1 |
| Flat Rock Gas LLC | 100829 | Ogden | 0 | 0 |
| Flatirons Resources, LLC | 100830 | Westminster | 0 | 0 |
| Fleet Energy LLC | 100831 | Houston | 4 | 2 |
| Flickinger & Echelman | 100832 | — | 2 | 1 |
| Florida Exploration Co | 100833 | Aurora | 3 | 2 |
| Flying Diamond Oil Corp | 100834 | — | 14 | 4 |
| Flying J Expl & Prod Inc | 100835 | N Salt Lake City | 0 | 0 |
| Flying J Inc | 100836 | Roosevelt | 5 | 2 |
| Flying J Oil & Gas Inc | 100837 | Roosevelt | 11 | 2 |
| Flying J Oil & Gas Inc | 100838 | N Salt Lake City | 0 | 0 |
| Forcenergy Inc | 100839 | Denver | 0 | 0 |
| Ford, Hugh W | 100840 | — | 1 | 1 |