# Relationship history for MSHA mine 1700538

Current hierarchy: **Ronald L  Farrin; Reginald G  Cobb; Kerry R  Farrin → Farrin Brothers & Smith Inc → Madison Pit & Plant**

- 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:** Farrin Brothers & Smith Inc → Madison Pit & Plant; 1981-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bruce  Farrin → Madison Pit & Plant; 1981-04-01 to 2016-07-05; source msha-controller-operator-history
- **controller_controls_operator:** Bruce  Farrin → Farrin Brothers & Smith Inc; 1981-04-01 to 2016-07-05; source msha-controller-operator-history
- **controller_controls_mine:** Ronald L  Farrin et al → Madison Pit & Plant; 2016-07-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ronald L  Farrin et al → Farrin Brothers & Smith Inc; 2016-07-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Reginald G  Cobb et al → Farrin Brothers & Smith Inc; 2016-07-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kerry R  Farrin et al → Farrin Brothers & Smith Inc; 2016-07-06 to current/open; source msha-controller-operator-history