# Relationship history for MSHA mine 3609856

Current hierarchy: **Clyde Holding Inc → Neiswonger Construction Inc → Sandy Plains**

- 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:** David C  Neiswonger et al → Sandy Plains; 2003-07-21 to 2020-04-24; source msha-controller-operator-history
- **operator_operates_mine:** Mon River Aggregates → Sandy Plains; 2010-07-28 to 2017-07-06; source msha-controller-operator-history
- **controller_controls_mine:** Thomas M  Boyle et al → Sandy Plains; 2010-07-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas M  Boyle et al → Mon River Aggregates; 2010-07-28 to 2017-07-06; source msha-controller-operator-history
- **operator_operates_mine:** Neiswonger Construction Inc → Sandy Plains; 2017-07-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David C  Neiswonger et al → Neiswonger Construction Inc; 2017-07-07 to 2020-04-24; source msha-controller-operator-history
- **controller_controls_mine:** Clyde Holding Inc → Sandy Plains; 2020-04-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Clyde Holding Inc → Neiswonger Construction Inc; 2020-04-25 to current/open; source msha-controller-operator-history