# Relationship history for MSHA mine 3400288

Current hierarchy: **Bruce L  Anderson → American Tripoli Inc → TRIPOLI**

- 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:** Carborundum Company → TRIPOLI; 1950-01-01 to 1981-06-03; source msha-controller-operator-history
- **controller_controls_mine:** Kennecott Copper Corp → TRIPOLI; 1950-01-01 to 1981-06-03; source msha-controller-operator-history
- **controller_controls_operator:** Kennecott Copper Corp → Carborundum Company; 1950-01-01 to 1981-06-03; source msha-controller-operator-history
- **operator_operates_mine:** Carborundum Company → TRIPOLI; 1981-06-04 to 1982-04-29; source msha-controller-operator-history
- **controller_controls_mine:** British Petroleum Company PLC → TRIPOLI; 1981-06-04 to 1982-04-29; source msha-controller-operator-history
- **controller_controls_operator:** British Petroleum Company PLC → Carborundum Company; 1981-06-04 to 1982-04-29; source msha-controller-operator-history
- **operator_operates_mine:** American Tripoli Company → TRIPOLI; 1982-04-30 to 1986-12-31; source msha-controller-operator-history
- **controller_controls_mine:** E M Warburg Pincus & Company Inc → TRIPOLI; 1982-04-30 to 1986-12-31; source msha-controller-operator-history
- **controller_controls_operator:** E M Warburg Pincus & Company Inc → American Tripoli Company; 1982-04-30 to 1986-12-31; source msha-controller-operator-history
- **operator_operates_mine:** American Tripoli Inc → TRIPOLI; 1987-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Fording Inc → TRIPOLI; 1987-01-01 to 2016-09-29; source msha-controller-operator-history
- **controller_controls_operator:** Fording Inc → American Tripoli Inc; 1987-01-01 to 2016-09-29; source msha-controller-operator-history
- **controller_controls_mine:** Bruce L  Anderson → TRIPOLI; 2016-09-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bruce L  Anderson → American Tripoli Inc; 2016-09-30 to current/open; source msha-controller-operator-history