# Relationship history for MSHA mine 0301414

Current hierarchy: **Neal Howard & Tobe Hummer → Material & Supplies Inc → Dugout Quarry**

- 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:** Mc Whorter O C → Dugout Quarry; 1950-01-01 to 1994-10-31; source msha-controller-operator-history
- **operator_operates_mine:** Hellcat Heights Inc → Dugout Quarry; 1978-07-01 to 1979-04-30; source msha-controller-operator-history
- **controller_controls_operator:** Mc Whorter O C → Hellcat Heights Inc; 1978-07-01 to 1979-04-30; source msha-controller-operator-history
- **operator_operates_mine:** Material & Supplies Inc → Dugout Quarry; 1979-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Neal Howard & Tobe Hummer → Dugout Quarry; 1979-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Neal Howard & Tobe Hummer → Material & Supplies Inc; 1979-05-01 to current/open; source msha-controller-operator-history