# Relationship history for MSHA mine 1509340

Current hierarchy: **Nicholas  Saylor → New Harlan Block Coal Company Inc → #2**

- 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:** Princess Anne Coal Company Inc → #2; 1950-01-01 to 1986-01-14; source msha-controller-operator-history
- **controller_controls_mine:** Sergent Birg E → #2; 1950-01-01 to 1986-01-14; source msha-controller-operator-history
- **controller_controls_operator:** Sergent Birg E → Princess Anne Coal Company Inc; 1950-01-01 to 1986-01-14; source msha-controller-operator-history
- **controller_controls_mine:** Nicholas  Saylor et al → #2; 1978-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** New Harlan Block Coal Company Inc → #2; 1986-01-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nicholas  Saylor et al → New Harlan Block Coal Company Inc; 1986-01-15 to current/open; source msha-controller-operator-history