# Relationship history for MSHA mine 0503950

Current hierarchy: **Kenneth  Smith → Smithco Construction & Excavation → GOODMAN PIT**

- 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:** Cobblestone Ltd → GOODMAN PIT; 1984-05-01 to 1991-06-04; source msha-controller-operator-history
- **controller_controls_mine:** Leonard W  Lloyd → GOODMAN PIT; 1984-05-01 to 1991-06-04; source msha-controller-operator-history
- **controller_controls_operator:** Leonard W  Lloyd → Cobblestone Ltd; 1984-05-01 to 1991-06-04; source msha-controller-operator-history
- **operator_operates_mine:** Smithco Gravel → GOODMAN PIT; 1991-06-05 to 1996-07-23; source msha-controller-operator-history
- **controller_controls_mine:** Kenneth  Smith → GOODMAN PIT; 1991-06-05 to 1996-07-23; source msha-controller-operator-history
- **controller_controls_operator:** Kenneth  Smith → Smithco Gravel; 1991-06-05 to 1996-07-23; source msha-controller-operator-history
- **operator_operates_mine:** Poma Excavating → GOODMAN PIT; 1996-07-24 to 1996-08-14; source msha-controller-operator-history
- **controller_controls_mine:** Anthony  Poma → GOODMAN PIT; 1996-07-24 to 1996-08-14; source msha-controller-operator-history
- **controller_controls_operator:** Anthony  Poma → Poma Excavating; 1996-07-24 to 1996-08-14; source msha-controller-operator-history
- **operator_operates_mine:** Smithco Construction & Excavation → GOODMAN PIT; 1996-08-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kenneth  Smith → GOODMAN PIT; 1996-08-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kenneth  Smith → Smithco Construction & Excavation; 1996-08-15 to current/open; source msha-controller-operator-history