- American Midstream Partners, LP
- Black Stone Minerals, L.P.
- Callon Petroleum Company
- Earthstone Energy, Inc.
- Energen Corporation
- Ensign Energy Services Inc.
- Erin Energy Corporation
- EV Energy Partners, L.P.
- Harvest Natural Resources, Inc.
- JP Energy Partners LP
- Par Pacific Holdings, Inc.
- PDC Energy, Inc.
- Resolute Energy Corporation
- Ring Energy, Inc.
- RSP Permian, Inc.
- Tesco Corporation
- TransMontaigne Partners L.P.
- VAALCO Energy, Inc.