# Relationship history for MSHA mine 2601560

Current hierarchy: **Peabody International → Peabody Calada Inc → Bird**

- 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:** Porter & Meissner Mining → Bird; 1979-09-01 to 1980-10-06; source msha-controller-operator-history
- **controller_controls_mine:** Meissner Donald O & Duane H Porter → Bird; 1979-09-01 to 1981-01-28; source msha-controller-operator-history
- **controller_controls_operator:** Meissner Donald O & Duane H Porter → Porter & Meissner Mining; 1979-09-01 to 1980-10-06; source msha-controller-operator-history
- **controller_controls_mine:** Peabody International → Bird; 1980-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Peabody Calada Inc → Bird; 1980-10-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Peabody International → Peabody Calada Inc; 1980-10-07 to current/open; source msha-controller-operator-history