# Relationship history for MSHA mine 4105478

Current hierarchy: **Matthew  Halfacer → H.D. Limestone → H.D. Limestone**

- 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:** H.D. Limestone → H.D. Limestone; 2019-12-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Coby  Davis et al → H.D. Limestone; 2019-12-16 to 2020-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Coby  Davis et al → H.D. Limestone; 2019-12-16 to 2020-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Matthew  Halfacer et al → H.D. Limestone; 2019-12-16 to 2020-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Matthew  Halfacer → H.D. Limestone; 2020-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Matthew  Halfacer → H.D. Limestone; 2020-06-01 to current/open; source msha-controller-operator-history