# Relationship history for MSHA mine 1202106

Current hierarchy: **Romero Richard → Northern Coal Company Inc → Rock Run**

- 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:** Graber Jesse Jr Et Al → Rock Run; 1987-11-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Marks Coal Company Inc → Rock Run; 1991-10-01 to 1993-08-06; source msha-controller-operator-history
- **controller_controls_operator:** Graber Jesse Jr Et Al → Marks Coal Company Inc; 1991-10-01 to 1993-08-06; source msha-controller-operator-history
- **controller_controls_mine:** Romero Richard → Rock Run; 1993-02-14 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Northern Coal Company Inc → Rock Run; 1993-08-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Romero Richard → Northern Coal Company Inc; 1993-08-07 to current/open; source msha-controller-operator-history