# Relationship history for MSHA mine 2900616

Current hierarchy: **Mock Harold → Six-M Concrete Company → Seneca Pit**

- 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:** Cliff House & Son → Seneca Pit; 1950-01-01 to 1980-03-31; source msha-controller-operator-history
- **controller_controls_mine:** House Cliff → Seneca Pit; 1950-01-01 to 1980-03-31; source msha-controller-operator-history
- **controller_controls_operator:** House Cliff → Cliff House & Son; 1950-01-01 to 1980-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Six-M Concrete Company → Seneca Pit; 1980-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mock Harold → Seneca Pit; 1980-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mock Harold → Six-M Concrete Company; 1980-04-01 to current/open; source msha-controller-operator-history