# Relationship history for MSHA mine 0405108

Current hierarchy: **Ted E  Contri; Ted E  Contri → Mercer Fraser Co → Mercer Fraser Plant B Portable Crusher**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Bott William F → Mercer Fraser Plant B Portable Crusher; 1950-01-01 to 2002-01-15; source msha-controller-operator-history
- **operator_operates_mine:** Canevari Timber Company → Mercer Fraser Plant B Portable Crusher; 1990-10-01 to 1997-06-30; source msha-controller-operator-history
- **controller_controls_mine:** Canevari Robert → Mercer Fraser Plant B Portable Crusher; 1990-10-01 to 1997-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Canevari Robert → Canevari Timber Company; 1990-10-01 to 1997-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Mercer Fraser Co → Mercer Fraser Plant B Portable Crusher; 1997-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bott William F → Mercer Fraser Co; 1997-07-01 to 2002-01-15; source msha-controller-operator-history
- **controller_controls_mine:** Ted E  Contri  et al → Mercer Fraser Plant B Portable Crusher; 2002-01-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ted E  Contri  et al → Mercer Fraser Co; 2002-01-16 to current/open; source msha-controller-operator-history