# Relationship history for MSHA mine 2601451

Current hierarchy: **Collins Timothy & Earl Haldeman → United Mining Company Of Nevada Inc → Umc American Flat Mill**

- 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:** Houston Oil & Minerals Corp → Umc American Flat Mill; 1950-01-01 to 1981-04-30; source msha-controller-operator-history
- **operator_operates_mine:** Houston International Minerals Corp → Umc American Flat Mill; 1978-03-09 to 1981-04-30; source msha-controller-operator-history
- **controller_controls_operator:** Houston Oil & Minerals Corp → Houston International Minerals Corp; 1978-03-09 to 1981-04-30; source msha-controller-operator-history
- **controller_controls_mine:** Collins Timothy & Earl Haldeman → Umc American Flat Mill; 1979-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Houston International Minerals Corp → Umc American Flat Mill; 1981-05-01 to 1983-01-30; source msha-controller-operator-history
- **controller_controls_mine:** Tenneco Inc → Umc American Flat Mill; 1981-05-01 to 1983-01-30; source msha-controller-operator-history
- **controller_controls_operator:** Tenneco Inc → Houston International Minerals Corp; 1981-05-01 to 1983-01-30; source msha-controller-operator-history
- **operator_operates_mine:** United Mining Company Of Nevada Inc → Umc American Flat Mill; 1983-01-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Collins Timothy & Earl Haldeman → United Mining Company Of Nevada Inc; 1983-01-31 to current/open; source msha-controller-operator-history