# Relationship history for MSHA mine 1516938

Current hierarchy: **Gray Dennis → Headache Coal Company Inc → #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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Hembree Robert → #1; 1987-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Larry  Hubbard  et al → #1; 1989-07-10 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Granny Rose Coal Company → #1; 1990-08-01 to 1990-08-26; source msha-controller-operator-history
- **controller_controls_operator:** Hembree Robert → Granny Rose Coal Company; 1990-08-01 to 1990-08-26; source msha-controller-operator-history
- **operator_operates_mine:** Gary Coal Mining → #1; 1990-08-27 to 1990-11-13; source msha-controller-operator-history
- **controller_controls_mine:** Miles Gary Et Al → #1; 1990-08-27 to 1990-11-13; source msha-controller-operator-history
- **controller_controls_operator:** Miles Gary Et Al → Gary Coal Mining; 1990-08-27 to 1990-11-13; source msha-controller-operator-history
- **operator_operates_mine:** C & H Mining → #1; 1990-11-14 to 1991-01-07; source msha-controller-operator-history
- **controller_controls_operator:** Larry  Hubbard  et al → C & H Mining; 1990-11-14 to 1991-01-07; source msha-controller-operator-history
- **controller_controls_operator:** Lloyd  Cole  et al → C & H Mining; 1990-11-14 to 1991-01-07; source msha-controller-operator-history
- **operator_operates_mine:** Michael Coal Company → #1; 1991-01-08 to 1992-01-21; source msha-controller-operator-history
- **controller_controls_mine:** Murphy Michael → #1; 1991-01-08 to 1992-01-21; source msha-controller-operator-history
- **controller_controls_operator:** Murphy Michael → Michael Coal Company; 1991-01-08 to 1992-01-21; source msha-controller-operator-history
- **operator_operates_mine:** Headache Coal Company Inc → #1; 1992-01-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gray Dennis → #1; 1992-01-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gray Dennis → Headache Coal Company Inc; 1992-01-22 to current/open; source msha-controller-operator-history