# Relationship history for MSHA mine 4607263

Current hierarchy: **Kniceley Ralph → Ralph Kniceley Construction → Blue Rock**

- 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:** Lilly D Dayton → Blue Rock; 1983-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Superior Mining Company → Blue Rock; 1987-03-01 to 1988-10-09; source msha-controller-operator-history
- **controller_controls_mine:** Shepler Thomas → Blue Rock; 1987-03-01 to 1988-10-09; source msha-controller-operator-history
- **controller_controls_operator:** Shepler Thomas → Superior Mining Company; 1987-03-01 to 1988-10-09; source msha-controller-operator-history
- **operator_operates_mine:** Lillybrook Coal Company → Blue Rock; 1988-10-10 to 1990-02-22; source msha-controller-operator-history
- **controller_controls_operator:** Lilly D Dayton → Lillybrook Coal Company; 1988-10-10 to 1990-02-22; source msha-controller-operator-history
- **operator_operates_mine:** Ralph Kniceley & Mark Cunningham Construction → Blue Rock; 1990-02-23 to 1994-11-21; source msha-controller-operator-history
- **controller_controls_mine:** Kniceley Ralph & Mark Cunningham → Blue Rock; 1990-02-23 to 1994-11-21; source msha-controller-operator-history
- **controller_controls_operator:** Kniceley Ralph & Mark Cunningham → Ralph Kniceley & Mark Cunningham Construction; 1990-02-23 to 1994-11-21; source msha-controller-operator-history
- **operator_operates_mine:** Ralph Kniceley Construction → Blue Rock; 1994-11-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kniceley Ralph → Blue Rock; 1994-11-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kniceley Ralph → Ralph Kniceley Construction; 1994-11-22 to current/open; source msha-controller-operator-history