# Relationship history for MSHA mine 1509636

Current hierarchy: **Sev.en Global Investments a.s. → Blue Diamond Coal Co → NO. 77**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Blue Diamond Coal Company → NO. 77; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Blue Diamond Coal Company → NO. 77; 1976-01-01 to 1993-06-03; source msha-controller-operator-history
- **controller_controls_operator:** Blue Diamond Coal Company → Blue Diamond Coal Company; 1976-01-01 to 1993-06-03; source msha-controller-operator-history
- **operator_operates_mine:** Altec Energy Inc → NO. 77; 1993-06-04 to 2000-06-01; source msha-controller-operator-history
- **controller_controls_mine:** Allen G  Stump et al → NO. 77; 1993-06-04 to 2001-03-07; source msha-controller-operator-history
- **controller_controls_operator:** Allen G  Stump et al → Altec Energy Inc; 1993-06-04 to 2000-06-01; source msha-controller-operator-history
- **controller_controls_mine:** James River Coal Company → NO. 77; 1998-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Blue Diamond Coal Company → NO. 77; 2000-06-02 to 2014-09-03; source msha-controller-operator-history
- **controller_controls_operator:** James River Coal Company → Blue Diamond Coal Company; 2000-06-02 to 2014-09-03; source msha-controller-operator-history
- **operator_operates_mine:** Blue Diamond Coal Co → NO. 77; 2014-09-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Blackhawk Mining LLC → NO. 77; 2014-09-04 to 2020-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Blackhawk Mining LLC → Blue Diamond Coal Co; 2014-09-04 to 2020-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Sev.en Global Investments a.s. → NO. 77; 2020-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sev.en Global Investments a.s. → Blue Diamond Coal Co; 2020-06-01 to current/open; source msha-controller-operator-history