# Relationship history for MSHA mine 1101818

Current hierarchy: **Ryan Matthew J → P W Ryan Sons Inc → Schlueter Quarry**

- 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:** Ryan Matthew J → Schlueter Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** H R Nott & Company → Schlueter Quarry; 1950-01-01 to 1981-05-03; source msha-controller-operator-history
- **controller_controls_mine:** Nott H R & Company → Schlueter Quarry; 1950-01-01 to 1981-05-03; source msha-controller-operator-history
- **controller_controls_operator:** Nott H R & Company → H R Nott & Company; 1950-01-01 to 1981-05-03; source msha-controller-operator-history
- **operator_operates_mine:** P W Ryan Sons Inc → Schlueter Quarry; 1981-05-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ryan Matthew J → P W Ryan Sons Inc; 1981-05-04 to current/open; source msha-controller-operator-history