# Relationship history for MSHA mine 1302134

Current hierarchy: **Mathy Construction Company → River City Stone Division Of Mathy Construction Co → Plant #20**

- 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:** Mathy Construction Company → Plant #20; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Don  Iverson et al → Plant #20; 1985-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** River City Stone Inc → Plant #20; 1985-10-01 to 1992-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Don  Iverson et al → River City Stone Inc; 1985-10-01 to 1992-03-31; source msha-controller-operator-history
- **operator_operates_mine:** River City Stone Division Of Mathy Construction Co → Plant #20; 1992-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mathy Construction Company → River City Stone Division Of Mathy Construction Co; 1992-04-01 to current/open; source msha-controller-operator-history