| Business | Phone |
| Elkhorn Operating Co 8801 S Yale Ave # 420, Tulsa 74137 | (918) 492-4418 |
| Enerfin Resources Co 7136 S Yale Ave # 414, Tulsa 74136 | (918) 492-8686 |
| Energy Service Investment Corp 9175 S Yale Ave # 210, Tulsa 74137 | (918) 492-7300 |
| Five Oaks Inc 8801 S Yale Ave # 420, Tulsa 74137 | (918) 492-4417 |