- Coral Production Corp
- Cordell Energy Corp
- Core Energy LLC
- Core Minerals Operating Co
- Corley Trust
- Cornelius Petroleum Inc
- Cornerston Energy
- Cornerstone Oil Trust
- Coronado Oil
- Coronado Oil Co
- Coronado Oil Co
- Corpening Enterprises
- Corpening Enterprises
- Corporate & Trustee Svc Inc
- Corporate Services Assoc
- Cortez Oil & Gas
- Corvette Oil Corp
- Cosenza Oil Co Inc
- Cosmo Oil Of USA Inc
- Cosmo Oil Of USA Inc
- Cotroneo Auto Group
- Cotton Valley Productions Inc
- Cotton Valley Productions Inc
- Cougar Oil Field
- Cougar Oil Inc
- Coulson Oil Co
- Coulson Oil Co
- Coury Oil Co Inc
- Cov Inc
- Covington Oil & Gas
- Covington Oil & Gas
- Cowboys D & D Oil
- Cowden Oil Co
- Cox Petroleum Co
- Coy Oil Inc
- Craig Oil Inc
- Crain & Deisenroth
- Crain Location
- Craves Oil Co
- Crawford County Oil
- Crawford County Oil
- Crawford County Oil
- Crawley Petroleum Corp
- CRD Oil Corp
- Crebbs Oil Co
- Cree Co
- Cree Co
- Cree Companies
- Creel & Assoc Inc
- Crenshaw Oil Co Inc
- Crescendo Resources
- Crescent Oil & Gas Co
- Crescent Oil Co
- Crescent Oil Co
- Crest Resources
- Creston Petroleum Corp
- Crestridge Drilling-Production
- Crimson Resource Management
- Crimson Resource Management
- Crimson Resource Management
- Crocker Oil Co
- Crocker Oil Co
- Croft Petroleum
- Croft Petroleum Co
- Croft Petroleum Co
- Croix Oil Co
- Crone Oil Co
- Crone Oil Co
- Crosby Creek Oil & Gas
- Crosby Creek Oil & Gas
- Crosby-Ms Resources
- Cross Coal/Whaleco Oil
- Cross Oil
- Cross Oil Co
- Cross Oil LLC
- Cross Timbers Operating Co
- Cross Timbers Operating Co
- Cross Timbers Operating Co
- Cross Timbers Operating Co
- Cross Timbers Operating Co
- Cross Timbers Operating Co
- Cross Timbers Operating Co
- Cross Timbers Operation Co
- Cross Timbers Production Co
- Cross Timbers Royalty Trust
- Cross Timbers Royalty Trust
- Crosstex Energy Inc
- Crosstex Energy Svc
- Crown Central Petroleum Corp
- Crown Oil
- Crown Oil Co
- Crown Quest Operating
- Crown Well Svc
- Crownquest
- Crownquest
- Crude Oil Co
- Crude Oil Purchasing-Preston
- Crystal Oil Inc
- Crystal River Oil & Gas
- Crystal River Oil & Gas
- Crystaline
- CTC Oil Inc
- CTL Oil & Gas
- Culp & Copple Oil Co
- Culp & Copple Shop
- Cumberland Valley Resource
- Cummings Oil Co
- Curt's Oil
- Curtis Little Oil & Gas
- Curtis Mc Kallip
- Cutler Interest
- Cutter Oil Co
- CXY Energy Inc
- CXY Energy Inc
- CXY Energy Inc
- Cyn Oil Corp
- Cyrstal River Oil & Gas LLC
- Cyrus Frost Oil Exploration
- D & B Oil Inc
- D & D Oil
- D & D Oil Co
- D & D Oil Field Rentals
- D & D Resources Inc
- D & E Oil Inc
- D & G Roustabout Svc
- D & J Oil Co
- D & R Oil Co
- D & R Oil Co
- D & S Falco
- D & S Hot Oil Svc
- D & S Oil
- D & S Oil & Gas Operators Inc
- D & T Swabbing Inc
- D C Energy Inc
- D D Dunlap Co
- D D Dunlap Co
- D J Simmons Inc
- D Jenkins Oil
- D K Boyd Oil & Gas Co
- D Michaud
- D P Operating Co
- D P Operating Co
- D R Lauck Oil Co
- D R Lauck Oil Co
- D R Lauck Oil Co
- D T Oil Station Inc
- D T Old Gas
- D W Dittman Oil Productions
- D-E-M Operations
- D-Mil Productions Inc
- Da Mar Resources Inc
- Daco
- Daco
- Dacus Oil Field Svc
- Dahab Energy Inc
- Dahl Oil Co
- Daigle Oil
- Dakota Crude
- Dakota Gasification Co
- Dakota Plains Co-Op
- Dale O Reese
- Dallas Oil Co
- Dallas Oil Group
- Dallas Petroleum Partners
- Dallas Production Inc
- Dalton & Hanna Co Oil & Gas
- Dalton H Cobb
- DAMSCO
- DAMSCO
- Dan J Harrison Jr
- Dan Reynolds Co
- Dan's Oil Inc
- Dane G Hansen Trust
- Daniels Oil Burning Svc
- Danmark Energy
- Danmark Energy
- Danube Co-Op Oil Co
- Danube Co-Op Oil Co
- Darden Oil Co
- Dark Horse Oil Co
- Darrah Oil
- Darst Creek Oil Co
- Darst Creek Oil Co
- Dart Oil & Gas
- Dash Production Co
- Dash Production Co
- Dash Production Co
- Dash Production Co
- Davcro Inc
- Davcro Inc
- Dave Gammill
- Davenport Oil
- David A Frawley
- David A Schlachter Oil
- David Crow Interests
- David Crow Interests
- David H Arrington Oil & Gas
- David L Atwell
- Davies Oil Co Inc
- Davis & Wardlaw Oil Co Inc
- Davis Brothers LLC
- Davis Oil
- Davis Petroleum Corp
- Davis Petroleum Corp
- Davis-Osage Corp
- Davison Oil & Gas
- Dawson Oil Co
- Day Oil Co
- Day Oil Co
- Daystar Oil & Gas
- Dazu Oil & Filter
- DDX Corp
- De Blois Oil Co
- De Mier Oil Co
- De Mier Oil Co
- De Mier Oil Co
- De Mier Oil Co
- De Mier Oil Co
- Dead River Co
- Deahan's Oil
- Deahan's Oil
- Dean Knight Oil Co Inc
- Dean Oil Co
- Dean Oil Co
- Dean Oil Refining
- Dean Pipeline Co
- Dearing Inc
- Dearybury Oil Inc
- Debra H Featherston
- Dec Energy Co
- Deck Oil Co
- Decor Co
- Dedica Energy Corp
- Dedica Energy Corp
- Dee Drilling Co
- Dee Drilling Co
- Deem Oil Co
- Deep Oil Technology
- Defazio Oil Data Lines
- Dehlinger Oil & Gas Inc
- Del Norte Petroleum
- Del Ray Oil Inc
- Delaney Oil
- Delco Oil Inc
- Dellconn Oil Corp
- Delmarva Oil Inc
- Delmarva Oil Inc
- Delmarve Oil Inc
- Delphi Oil
- Delray Oil Inc Luling District
- Delta Operating Corp
- Delta Petroleum Corp
- Delta Royalty Co
- Demartini Oil Equipment Svc
- Dempsey Oil Co
- Dempsey Oil Co
- Denbury Management Inc
- Denbury Management Inc
- Denbury Management Inc
- Denbury Onshore LLC
- Denbury Resources
- Denbury Resources
- Denbury Resources Inc
- Denbury Resources Inc
- Denbury Resources Inc
- Denbury Resources Inc
- Denbury Resources Inc
- Denbury Resources Inc
- Denbury Resources Inc
- Denbury Resources Inc
- Dennis Oil & Rental Co
- Denson Oil
- Derrick Petroleum
- Desoto Oil & Gas Inc
- Destin Operating Co Inc
- Devi Oil Inc
- Devon
- Devon Energy Co
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
- Devon Energy Corp
