# Relationship history for MSHA mine 1514990

Current hierarchy: **Koch Industries Inc → Koch Carbon Inc → Warco #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:** Koch Industries Inc → Warco #1; 1979-05-31 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Warco Mining Company Inc → Warco #1; 1984-11-01 to 1989-04-05; source msha-controller-operator-history
- **controller_controls_mine:** Larry  Thornsberry et al → Warco #1; 1984-11-01 to 1989-04-05; source msha-controller-operator-history
- **controller_controls_operator:** Larry  Thornsberry et al → Warco Mining Company Inc; 1984-11-01 to 1989-04-05; source msha-controller-operator-history
- **controller_controls_mine:** Ernest E  Varney et al → Warco #1; 1988-08-22 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Koch Carbon Inc → Warco #1; 1989-04-06 to 1989-08-25; source msha-controller-operator-history
- **controller_controls_operator:** Koch Industries Inc → Koch Carbon Inc; 1989-04-06 to 1989-08-25; source msha-controller-operator-history
- **operator_operates_mine:** Black Widow Collieries Ltd → Warco #1; 1989-08-26 to 1990-01-24; source msha-controller-operator-history
- **controller_controls_operator:** Ernest E  Varney et al → Black Widow Collieries Ltd; 1989-08-26 to 1990-01-24; source msha-controller-operator-history
- **operator_operates_mine:** Koch Carbon Inc → Warco #1; 1990-01-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Koch Industries Inc → Koch Carbon Inc; 1990-01-25 to current/open; source msha-controller-operator-history