# Relationship history for MSHA mine 4502807

Current hierarchy: **Kimball  Storedahl; Kevin  Storedahl → J L Storedahl & Sons Inc → Portable 4**

- 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:** Mary  Riley → Portable 4; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ostrander Rock & Construction Company Inc → Portable 4; 1981-06-01 to 1987-09-01; source msha-controller-operator-history
- **controller_controls_operator:** Mary  Riley → Ostrander Rock & Construction Company Inc; 1981-06-01 to 1987-09-01; source msha-controller-operator-history
- **controller_controls_mine:** Jerry L  Storedahl → Portable 4; 1985-06-18 to 2018-12-31; source msha-controller-operator-history
- **operator_operates_mine:** J L Storedahl & Sons Inc → Portable 4; 1987-09-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jerry L  Storedahl → J L Storedahl & Sons Inc; 1987-09-02 to 2018-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Kimball  Storedahl et al → Portable 4; 2019-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kimball  Storedahl et al → J L Storedahl & Sons Inc; 2019-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kevin  Storedahl et al → J L Storedahl & Sons Inc; 2019-01-01 to current/open; source msha-controller-operator-history