# Relationship history for MSHA mine 1516256

Current hierarchy: **Nicholas  Saylor → New Harlan Block Coal Company Inc → N H B #3**

- 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:** Nicholas  Saylor et al → N H B #3; 1978-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** New Harlan Block Coal Company Inc → N H B #3; 1987-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nicholas  Saylor et al → New Harlan Block Coal Company Inc; 1987-11-01 to current/open; source msha-controller-operator-history