# Relationship history for MSHA mine 3605604

Current hierarchy: **Graham Maynard-Glen & Donald Cummings → Graham Brothers Coal Company → Egypt #2 Strip**

- 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:** Graham Brothers Coal Company → Egypt #2 Strip; 1975-05-12 to 1976-07-31; source msha-controller-operator-history
- **controller_controls_mine:** Graham Bruce → Egypt #2 Strip; 1975-05-12 to 1976-07-31; source msha-controller-operator-history
- **controller_controls_operator:** Graham Bruce → Graham Brothers Coal Company; 1975-05-12 to 1976-07-31; source msha-controller-operator-history
- **operator_operates_mine:** Graham Brothers Coal Company → Egypt #2 Strip; 1976-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Graham Maynard-Glen & Donald Cummings → Egypt #2 Strip; 1976-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Graham Maynard-Glen & Donald Cummings → Graham Brothers Coal Company; 1976-08-01 to current/open; source msha-controller-operator-history