# Relationship history for MSHA mine 4605996

Current hierarchy: **Keeney Robert H → Mikela Corp → Mikela Corp**

- 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:** Ace Coal Sales Inc → Mikela Corp; 1979-05-01 to 1980-10-22; source msha-controller-operator-history
- **controller_controls_mine:** Martin Carl J → Mikela Corp; 1979-05-01 to 1980-10-22; source msha-controller-operator-history
- **controller_controls_operator:** Martin Carl J → Ace Coal Sales Inc; 1979-05-01 to 1980-10-22; source msha-controller-operator-history
- **operator_operates_mine:** Mikela Corp → Mikela Corp; 1980-10-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Keeney Robert H → Mikela Corp; 1980-10-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Keeney Robert H → Mikela Corp; 1980-10-23 to current/open; source msha-controller-operator-history