# Relationship history for MSHA mine 1512149

Current hierarchy: **Lawson David & Kenneth--James Baird → L & B Coal Company Inc → L & B #1**

- 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

- **operator_operates_mine:** Chaney Creek Coal Corp → L & B #1; 1979-11-01 to 1981-06-05; source msha-controller-operator-history
- **controller_controls_mine:** Chaney John → L & B #1; 1979-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Chaney John → Chaney Creek Coal Corp; 1979-11-01 to 1981-06-05; source msha-controller-operator-history
- **operator_operates_mine:** L & B Coal Company Inc → L & B #1; 1981-06-06 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Lawson David & Kenneth--James Baird → L & B #1; 1981-06-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lawson David & Kenneth--James Baird → L & B Coal Company Inc; 1981-06-06 to current/open; source msha-controller-operator-history