HARRISBURG — Natural gas companies are expected to be on the hook for millions of dollars in unpaid state “impact fees” after a ruling by the Pennsylvania Supreme Court.

A Pittsburgh newspaper reports that Pennsylvania utility regulators are generating invoices for some 17 shale gas producers that had challenged fees on some of their wells. The dispute centered on what counts as a “stripper well” — a well nearing the end of its life. Such wells are exempt from impact fees.

Drillers had argued for a more expansive definition of the term, meaning more wells would be exempt from the fees, but the Supreme Court disagreed.