# Relationship history for MSHA mine 2601273

Current hierarchy: **Martin Marietta Materials Inc → Sha-Neva Inc → Lemmon Valley Portable Plant**

- 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:** Sha-Neva Inc → Lemmon Valley Portable Plant; 1950-01-01 to 2001-08-09; source msha-controller-operator-history
- **controller_controls_mine:** Kelly  Shane et al → Lemmon Valley Portable Plant; 1950-01-01 to 2001-08-09; source msha-controller-operator-history
- **controller_controls_operator:** Kelly  Shane et al → Sha-Neva Inc; 1950-01-01 to 2001-08-09; source msha-controller-operator-history
- **operator_operates_mine:** Sha-Neva Inc → Lemmon Valley Portable Plant; 2001-08-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Lemmon Valley Portable Plant; 2001-08-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Sha-Neva Inc; 2001-08-10 to current/open; source msha-controller-operator-history