# Relationship history for MSHA mine 3606990

Current hierarchy: **Ronald  Lickman → Harriman Coal Corp → Lincoln Stripping**

- 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:** Hughes Contracting Company → Lincoln Stripping; 1980-06-01 to 1984-07-15; source msha-controller-operator-history
- **controller_controls_mine:** Joseph R  Hughes et al → Lincoln Stripping; 1980-06-01 to 1986-07-27; source msha-controller-operator-history
- **controller_controls_operator:** Joseph R  Hughes et al → Hughes Contracting Company; 1980-06-01 to 1984-07-15; source msha-controller-operator-history
- **operator_operates_mine:** Harriman Coal Corp → Lincoln Stripping; 1984-07-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ronald  Lickman → Lincoln Stripping; 1984-07-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ronald  Lickman → Harriman Coal Corp; 1984-07-16 to current/open; source msha-controller-operator-history