W. Va. Code R. § 85-17-7
This rule shall have no force and effect over private carriers and self-insured employers. However, a private carrier or self-insured employer may establish its own program regarding payment of workers' compensation benefits to claimants or payments of invoices to vendors by electronic means. Nothing herein shall permit any private carrier or self-insured employer to pay a claimant less than the required benefit rate set by statute or pay a provider less than the amount established by the Insurance Commissioner's fee schedule or the rate negotiated pursuant to a preferred provider, managed care, or other medical cost containment relationship with providers of medical, hospital, or other health care as permitted by W. Va. Code § 23-4-3, if applicable.
W. Va. Code R. § 85-17-7