# Relationship history for MSHA mine 2103012

Current hierarchy: **Hill Philip → Philip Hill Construction → Frank Staples Gravel 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Philip Hill Construction → Frank Staples Gravel Pit; 1990-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hill Philip → Frank Staples Gravel Pit; 1990-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hill Philip → Philip Hill Construction; 1990-07-01 to current/open; source msha-controller-operator-history