# Relationship history for MSHA mine 3601868

Current hierarchy: **Petersville Sleigh Ltd → A & T Associates Inc → Donaldson Coal Company**

- 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:** Industrial Coal Sales → Donaldson Coal Company; 1950-01-01 to 1976-07-29; source msha-controller-operator-history
- **controller_controls_mine:** Industrial Coal Sales → Donaldson Coal Company; 1950-01-01 to 1976-07-29; source msha-controller-operator-history
- **controller_controls_operator:** Industrial Coal Sales → Industrial Coal Sales; 1950-01-01 to 1976-07-29; source msha-controller-operator-history
- **controller_controls_mine:** Adams Donald H Sr → Donaldson Coal Company; 1975-03-27 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** A & T Associates Inc → Donaldson Coal Company; 1976-07-30 to 1980-05-22; source msha-controller-operator-history
- **controller_controls_operator:** Adams Donald H Sr → A & T Associates Inc; 1976-07-30 to 1980-05-22; source msha-controller-operator-history
- **operator_operates_mine:** A & T Associates Inc → Donaldson Coal Company; 1980-05-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Petersville Sleigh Ltd Et Al → Donaldson Coal Company; 1980-05-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Petersville Sleigh Ltd Et Al → A & T Associates Inc; 1980-05-23 to current/open; source msha-controller-operator-history