# Relationship history for MSHA mine 3102210

Current hierarchy: **David R Boyd → Max Boyd & Son Stone  Co → Dove Gray**

- 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:** Max Boyd & Son Stone  Co → Dove Gray; 2006-03-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** David R Boyd  et al → Dove Gray; 2006-03-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David R Boyd  et al → Max Boyd & Son Stone  Co; 2006-03-14 to current/open; source msha-controller-operator-history