# Relationship history for MSHA mine 0503174

Current hierarchy: **Zanett Richard G → Z M K Mining Company → Valley Forge Mine**

- 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:** Animas Canyon Mining Company → Valley Forge Mine; 1978-03-09 to 1980-07-23; source msha-controller-operator-history
- **controller_controls_mine:** Mc Kinney Ted D → Valley Forge Mine; 1978-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mc Kinney Ted D → Animas Canyon Mining Company; 1978-03-09 to 1980-07-23; source msha-controller-operator-history
- **operator_operates_mine:** Z M K Mining Company → Valley Forge Mine; 1980-07-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Zanett Richard G → Valley Forge Mine; 1980-07-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Zanett Richard G → Z M K Mining Company; 1980-07-24 to current/open; source msha-controller-operator-history