# Relationship history for MSHA mine 1512108

Current hierarchy: **Stivers Agnes H → Tinker Branch Coal Company Inc → No 1 Mine**

- 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:** Push & Grunt Coal Company Inc → No 1 Mine; 1979-10-01 to 1980-06-22; source msha-controller-operator-history
- **controller_controls_mine:** Riggs Robert F → No 1 Mine; 1979-10-01 to 1982-09-27; source msha-controller-operator-history
- **controller_controls_operator:** Riggs Robert F → Push & Grunt Coal Company Inc; 1979-10-01 to 1980-06-22; source msha-controller-operator-history
- **operator_operates_mine:** Dezarn Coal Company → No 1 Mine; 1980-06-23 to 1981-08-13; source msha-controller-operator-history
- **controller_controls_mine:** Dezarn Denzil & Dale → No 1 Mine; 1980-06-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dezarn Denzil & Dale → Dezarn Coal Company; 1980-06-23 to 1981-08-13; source msha-controller-operator-history
- **controller_controls_mine:** Baker Frank D-Doug Hopkin Et Al → No 1 Mine; 1981-08-01 to 1982-07-28; source msha-controller-operator-history
- **operator_operates_mine:** B H B Inc → No 1 Mine; 1981-08-14 to 1981-11-02; source msha-controller-operator-history
- **controller_controls_operator:** Baker Frank D-Doug Hopkin Et Al → B H B Inc; 1981-08-14 to 1981-11-02; source msha-controller-operator-history
- **operator_operates_mine:** Dezarn Coal Company → No 1 Mine; 1981-11-03 to 1982-07-20; source msha-controller-operator-history
- **controller_controls_operator:** Dezarn Denzil & Dale → Dezarn Coal Company; 1981-11-03 to 1982-07-20; source msha-controller-operator-history
- **operator_operates_mine:** Tinker Branch Coal Company Inc → No 1 Mine; 1982-07-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Stivers Agnes H → No 1 Mine; 1982-07-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stivers Agnes H → Tinker Branch Coal Company Inc; 1982-07-21 to current/open; source msha-controller-operator-history