# Relationship history for MSHA mine 1511737

Current hierarchy: **Nantz Charles → Nantz Coal → _**

- 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:** Bizzack John → _; 1974-10-18 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** B W H Coal Inc → _; 1979-02-01 to 1981-01-11; source msha-controller-operator-history
- **controller_controls_operator:** Bizzack John → B W H Coal Inc; 1979-02-01 to 1981-01-11; source msha-controller-operator-history
- **operator_operates_mine:** B W H Coal Inc → _; 1981-01-12 to 1983-06-06; source msha-controller-operator-history
- **controller_controls_mine:** Lewis Logan → _; 1981-01-12 to 1983-06-06; source msha-controller-operator-history
- **controller_controls_operator:** Lewis Logan → B W H Coal Inc; 1981-01-12 to 1983-06-06; source msha-controller-operator-history
- **operator_operates_mine:** N S & D Construction → _; 1983-06-07 to 1983-09-19; source msha-controller-operator-history
- **controller_controls_mine:** Nantz Bobby M Et Al → _; 1983-06-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nantz Bobby M Et Al → N S & D Construction; 1983-06-07 to 1983-09-19; source msha-controller-operator-history
- **operator_operates_mine:** Nantz Coal → _; 1983-09-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Nantz Charles Et Al → _; 1983-09-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nantz Charles Et Al → Nantz Coal; 1983-09-20 to current/open; source msha-controller-operator-history