# Relationship history for MSHA mine 4404934

Current hierarchy: **Tiller G O → D S & M Coal Corp → No 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

- **operator_operates_mine:** H & M Coal Company → No 1; 1978-01-01 to 1979-04-29; source msha-controller-operator-history
- **controller_controls_mine:** Mullins Dennis--Leon F Ramsey & Leon Beaver → No 1; 1978-01-01 to 1979-04-29; source msha-controller-operator-history
- **controller_controls_operator:** Mullins Dennis--Leon F Ramsey & Leon Beaver → H & M Coal Company; 1978-01-01 to 1979-04-29; source msha-controller-operator-history
- **operator_operates_mine:** D S & M Coal Corp → No 1; 1979-04-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tiller G O → No 1; 1979-04-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tiller G O → D S & M Coal Corp; 1979-04-30 to current/open; source msha-controller-operator-history