# Relationship history for MSHA mine 3503284

Current hierarchy: **Michael L  Houck → Crusher Dawgs Inc → Crusher Dawgs Inc**

- 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:** Michael L  Houck → Crusher Dawgs Inc; 1985-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** M L Houck Construction Company Inc → Crusher Dawgs Inc; 1987-04-01 to 1992-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Michael L  Houck → M L Houck Construction Company Inc; 1987-04-01 to 1992-09-30; source msha-controller-operator-history
- **operator_operates_mine:** T B Inc → Crusher Dawgs Inc; 1992-10-01 to 1998-04-09; source msha-controller-operator-history
- **controller_controls_mine:** Pamela  Houck → Crusher Dawgs Inc; 1992-10-01 to 1998-04-09; source msha-controller-operator-history
- **controller_controls_operator:** Pamela  Houck → T B Inc; 1992-10-01 to 1998-04-09; source msha-controller-operator-history
- **operator_operates_mine:** Crusher Dawgs Inc → Crusher Dawgs Inc; 1998-04-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Michael L  Houck → Crusher Dawgs Inc; 1998-04-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael L  Houck → Crusher Dawgs Inc; 1998-04-10 to current/open; source msha-controller-operator-history