Pay and discharge promptly when due all federal, state and other material Taxes, imposed upon it or upon its income or profits or in respect of its property, before any penalty or fine accrues thereon, as well as all lawful claims which, if unpaid, might give rise to a Lien (other than a Permitted Lien) upon such properties or any part thereof; provided, however, that such payment and discharge shall not be required with respect to any such Tax or claim so long as (a) the validity or amount thereof shall be contested in good faith by appropriate proceedings, and Holdings, the Borrower or the affected Subsidiary, as applicable, shall have set aside on its books reserves in accordance with GAAP with respect thereto and (b) in the case of a Tax or claim which has or may become a Lien against any of the Collateral, such contest proceedings conclusively operate to stay the sale of any portion of the Collateral to satisfy such Tax or claim. No Loan Party will, nor will it permit any of its Subsidiaries to, file or consent to the filing of any consolidated income tax return with any Person (other than Verso Corporation, Holdings or any of their respective Subsidiaries).