# Relationship history for MSHA mine 0102691

Current hierarchy: **Acuff Philip & Rudolph Roder → Parr Industries Inc → Abrasive Products Mobile Plant**

- 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:** Dravo Corp → Abrasive Products Mobile Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Dravo Basic Materials Company Inc → Abrasive Products Mobile Plant; 1986-07-01 to 1991-11-07; source msha-controller-operator-history
- **controller_controls_operator:** Dravo Corp → Dravo Basic Materials Company Inc; 1986-07-01 to 1991-11-07; source msha-controller-operator-history
- **operator_operates_mine:** Parr Industries Inc → Abrasive Products Mobile Plant; 1991-11-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Acuff Philip & Rudolph Roder → Abrasive Products Mobile Plant; 1991-11-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Acuff Philip & Rudolph Roder → Parr Industries Inc; 1991-11-08 to current/open; source msha-controller-operator-history