# Relationship history for MSHA mine 0201776

Current hierarchy: **Tanner Companies → Tanner Companies → Plant No 5**

- 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:** Tanner Companies → Plant No 5; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Sand Specialties → Plant No 5; 1950-01-01 to 1978-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Sand Specialties → Plant No 5; 1950-01-01 to 1979-06-19; source msha-controller-operator-history
- **controller_controls_operator:** Sand Specialties → Sand Specialties; 1950-01-01 to 1978-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Tanner Companies → Plant No 5; 1978-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tanner Companies → Tanner Companies; 1978-04-01 to current/open; source msha-controller-operator-history