Active Illinois Basin Operators

The Illinois Basin operator base is dominated by long-tenured small private and family-owned independents rather than public mid-cap producers. Public Illinois Department of Natural Resources, Indiana Division of Oil & Gas, and Kentucky Department of Oil & Gas Conservation filings show ongoing 2026 activity from the following operators among others:

Brothers Oil & Iron (BOI) — Evansville, IN; Rice family-backed buyer of legacy producing wells across the basin

Continental Resources of Illinois — Illinois-focused independent (distinct from Continental Resources Inc.)

Triple-S Petroleum — Western Kentucky and Southern Indiana operator

Hardesty Oil & Gas — Multi-state Illinois Basin operator

Cypress Creek Resources — Illinois Basin independent

Magnum Hunter Resources — selective Illinois Basin positions

Citation Oil & Gas — Illinois Basin and broader Mid-Continent independent

Smith Trust Properties — Family-trust-owned Illinois Basin operator

Energy Industries Inc. — Illinois-based small-operator

Wabash Valley Resources — Carbon capture and sequestration operator (CCS, not conventional E&P)

Additional small-operator activity from privately-held Illinois Basin independents that file individually with state regulators.