# Relationship history for MSHA mine 1516943

Current hierarchy: **Shackleford Michael → Dorco Mining Inc → #1 Mine**

- 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:** Warren Donnie → #1 Mine; 1990-01-22 to 1991-04-14; source msha-controller-operator-history
- **operator_operates_mine:** Beechnut Mining Inc → #1 Mine; 1990-08-01 to 1991-03-10; source msha-controller-operator-history
- **controller_controls_operator:** Warren Donnie → Beechnut Mining Inc; 1990-08-01 to 1991-03-10; source msha-controller-operator-history
- **operator_operates_mine:** Daily Contracting Inc → #1 Mine; 1991-03-11 to 1991-07-10; source msha-controller-operator-history
- **controller_controls_mine:** Warren Dewey → #1 Mine; 1991-03-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Warren Dewey → Daily Contracting Inc; 1991-03-11 to 1991-07-10; source msha-controller-operator-history
- **operator_operates_mine:** Dorco Mining Inc → #1 Mine; 1991-07-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Shackleford Michael → #1 Mine; 1991-07-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shackleford Michael → Dorco Mining Inc; 1991-07-11 to current/open; source msha-controller-operator-history