# Relationship history for MSHA mine 0403906

Current hierarchy: **Ricci M W & Elizabeth → M W Ricci → Golden Slide Mines**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** O C Nelson → Golden Slide Mines; 1980-02-01 to 1987-01-01; source msha-controller-operator-history
- **controller_controls_mine:** Nelson O C Et Al → Golden Slide Mines; 1980-02-01 to 1987-01-01; source msha-controller-operator-history
- **controller_controls_operator:** Nelson O C Et Al → O C Nelson; 1980-02-01 to 1987-01-01; source msha-controller-operator-history
- **controller_controls_mine:** Johnson Richard → Golden Slide Mines; 1985-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Dreamland Mining Company → Golden Slide Mines; 1987-01-02 to 1991-03-29; source msha-controller-operator-history
- **controller_controls_operator:** Johnson Richard → Dreamland Mining Company; 1987-01-02 to 1991-03-29; source msha-controller-operator-history
- **operator_operates_mine:** M W Ricci → Golden Slide Mines; 1991-03-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ricci M W & Elizabeth → Golden Slide Mines; 1991-03-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ricci M W & Elizabeth → M W Ricci; 1991-03-30 to current/open; source msha-controller-operator-history