# Relationship history for MSHA mine 1509839

Current hierarchy: **Jackson Roy Dan → Dry Lake Coal Company Inc → No6 Mine**

- 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:** Jackson Roy Dan → No6 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Dry Lake Coal Company Inc → No6 Mine; 1976-07-23 to 1978-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Jackson Roy Dan → Dry Lake Coal Company Inc; 1976-07-23 to 1978-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Dry Lake Coal Company Inc → No6 Mine; 1978-04-01 to 1980-03-05; source msha-controller-operator-history
- **controller_controls_mine:** Turner Charles & Bobby Joe Hensley → No6 Mine; 1978-04-01 to 1980-03-05; source msha-controller-operator-history
- **controller_controls_operator:** Turner Charles & Bobby Joe Hensley → Dry Lake Coal Company Inc; 1978-04-01 to 1980-03-05; source msha-controller-operator-history
- **operator_operates_mine:** Dry Lake Coal Company Inc → No6 Mine; 1980-03-06 to 1981-08-25; source msha-controller-operator-history
- **controller_controls_operator:** Jackson Roy Dan → Dry Lake Coal Company Inc; 1980-03-06 to 1981-08-25; source msha-controller-operator-history
- **controller_controls_mine:** Vandagriff Glen Doil → No6 Mine; 1981-02-24 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** G V Coal Company → No6 Mine; 1981-08-26 to 1981-12-03; source msha-controller-operator-history
- **controller_controls_operator:** Vandagriff Glen Doil → G V Coal Company; 1981-08-26 to 1981-12-03; source msha-controller-operator-history
- **operator_operates_mine:** Dry Lake Coal Company Inc → No6 Mine; 1981-12-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jackson Roy Dan → Dry Lake Coal Company Inc; 1981-12-04 to current/open; source msha-controller-operator-history