# Relationship history for MSHA mine 3608691

Current hierarchy: **Martinelli Frank → G & M Excavating Inc → Upper Lehigh**

- 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:** Devil'S Hole Inc → Upper Lehigh; 1997-08-01 to 1999-01-17; source msha-controller-operator-history
- **operator_operates_mine:** G & M Excavating Inc → Upper Lehigh; 1999-01-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Martinelli Frank → Upper Lehigh; 1999-01-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martinelli Frank → G & M Excavating Inc; 1999-01-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gene B  Gangloff → Upper Lehigh; 2002-05-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gene B  Gangloff → Devil'S Hole Inc; 2002-05-14 to 1999-01-17; source msha-controller-operator-history