# Relationship history for MSHA mine 4606068

Current hierarchy: **Hamilton Jack F → Hamdyn Coal Company Inc → Bemis Ron**

- 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:** Nardulli James A → Bemis Ron; 1977-06-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Glade Mill Coal Company Inc → Bemis Ron; 1979-12-01 to 1980-04-28; source msha-controller-operator-history
- **controller_controls_operator:** Nardulli James A → Glade Mill Coal Company Inc; 1979-12-01 to 1980-04-28; source msha-controller-operator-history
- **operator_operates_mine:** Hamdyn Coal Company Inc → Bemis Ron; 1980-04-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hamilton Jack F → Bemis Ron; 1980-04-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hamilton Jack F → Hamdyn Coal Company Inc; 1980-04-29 to current/open; source msha-controller-operator-history