# Relationship history for MSHA mine 4603266

Current hierarchy: **Holbrook Marjorie → Con-Serv Inc → Prep 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Youngstown Mines Corp → Prep Plant; 1950-01-01 to 1979-03-01; source msha-controller-operator-history
- **controller_controls_mine:** Lykes Resources Inc → Prep Plant; 1950-01-01 to 1979-07-18; source msha-controller-operator-history
- **controller_controls_operator:** Lykes Resources Inc → Youngstown Mines Corp; 1950-01-01 to 1979-03-01; source msha-controller-operator-history
- **controller_controls_mine:** LTV Corporation → Prep Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Jones & Laughlin Steel Corp → Prep Plant; 1979-03-02 to 1982-05-20; source msha-controller-operator-history
- **controller_controls_operator:** LTV Corporation → Jones & Laughlin Steel Corp; 1979-03-02 to 1982-05-20; source msha-controller-operator-history
- **operator_operates_mine:** Dehue Coal Company → Prep Plant; 1982-05-21 to 1984-11-13; source msha-controller-operator-history
- **controller_controls_mine:** Sidney R  Young III → Prep Plant; 1982-05-21 to 1984-11-19; source msha-controller-operator-history
- **controller_controls_operator:** Sidney R  Young III → Dehue Coal Company; 1982-05-21 to 1984-11-13; source msha-controller-operator-history
- **controller_controls_mine:** James B  Simpkins → Prep Plant; 1984-05-04 to 1988-01-17; source msha-controller-operator-history
- **operator_operates_mine:** Dehue Coal Company → Prep Plant; 1984-11-14 to 1985-10-31; source msha-controller-operator-history
- **controller_controls_mine:** Massey Energy Company → Prep Plant; 1984-11-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Dehue Coal Company; 1984-11-14 to 1985-10-31; source msha-controller-operator-history
- **operator_operates_mine:** Berachah Mining Inc → Prep Plant; 1985-11-01 to 1988-01-17; source msha-controller-operator-history
- **controller_controls_operator:** James B  Simpkins → Berachah Mining Inc; 1985-11-01 to 1988-01-17; source msha-controller-operator-history
- **operator_operates_mine:** Berachah Mining Inc → Prep Plant; 1988-01-18 to 1989-08-17; source msha-controller-operator-history
- **controller_controls_mine:** Conner Glen Jr → Prep Plant; 1988-01-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Conner Glen Jr → Berachah Mining Inc; 1988-01-18 to 1989-08-17; source msha-controller-operator-history
- **operator_operates_mine:** Con-Serv Inc → Prep Plant; 1989-08-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Holbrook Marjorie → Prep Plant; 1989-08-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Holbrook Marjorie → Con-Serv Inc; 1989-08-18 to current/open; source msha-controller-operator-history