# Relationship history for MSHA mine 3607760

Current hierarchy: **Lucas Gary → Aka Coal Company → Diamond Slope**

- 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

- **operator_operates_mine:** Lehman Coal Company → Diamond Slope; 1985-11-01 to 1986-07-23; source msha-controller-operator-history
- **controller_controls_mine:** Donofrio Robert Et Al → Diamond Slope; 1985-11-01 to 1986-07-23; source msha-controller-operator-history
- **controller_controls_operator:** Donofrio Robert Et Al → Lehman Coal Company; 1985-11-01 to 1986-07-23; source msha-controller-operator-history
- **operator_operates_mine:** Aka Coal Inc → Diamond Slope; 1986-07-24 to 1988-11-20; source msha-controller-operator-history
- **controller_controls_mine:** Adams Dale → Diamond Slope; 1986-07-24 to 1988-11-20; source msha-controller-operator-history
- **controller_controls_operator:** Adams Dale → Aka Coal Inc; 1986-07-24 to 1988-11-20; source msha-controller-operator-history
- **operator_operates_mine:** Aka Coal Inc → Diamond Slope; 1988-11-21 to 1989-03-26; source msha-controller-operator-history
- **controller_controls_mine:** Lettich Gene A Et Al → Diamond Slope; 1988-11-21 to 1989-03-26; source msha-controller-operator-history
- **controller_controls_operator:** Lettich Gene A Et Al → Aka Coal Inc; 1988-11-21 to 1989-03-26; source msha-controller-operator-history
- **operator_operates_mine:** Aka Coal Company → Diamond Slope; 1989-03-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Lucas Gary Et Al → Diamond Slope; 1989-03-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lucas Gary Et Al → Aka Coal Company; 1989-03-27 to current/open; source msha-controller-operator-history