# Relationship history for MSHA mine 0900837

Current hierarchy: **Highlands Coal & Chemical Corp → Gilbreath Creek Coal Company Inc → Gilbreath Creek No 1**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Canamex Coal Corp → Gilbreath Creek No 1; 1976-05-01 to 1978-07-11; source msha-controller-operator-history
- **controller_controls_mine:** Canamex Commodity Corp → Gilbreath Creek No 1; 1976-05-01 to 1978-07-11; source msha-controller-operator-history
- **controller_controls_operator:** Canamex Commodity Corp → Canamex Coal Corp; 1976-05-01 to 1978-07-11; source msha-controller-operator-history
- **operator_operates_mine:** Gilbreath Creek Coal Company Inc → Gilbreath Creek No 1; 1978-07-12 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Highlands Coal & Chemical Corp → Gilbreath Creek No 1; 1978-07-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Highlands Coal & Chemical Corp → Gilbreath Creek Coal Company Inc; 1978-07-12 to current/open; source msha-controller-operator-history