Each Credit Party shall pay all Taxes imposed upon it or any of its properties or assets or in respect of any of its income, businesses or franchises before any penalty or fine accrues thereon, and all claims (including claims for labor, services, materials and supplies) for sums that have become due and payable and that by Law have or may become a Lien upon any of its properties or assets, prior to the time when any penalty or fine shall be incurred with respect thereto, except where the failure to do so would not reasonably be expected to result in material liabilities to a Credit Party ; provided , (a) no such Tax or claim need be paid if it is being contested in good faith by appropriate proceedings promptly instituted and diligently conducted, so long as adequate reserve or other appropriate provision, as shall be required in conformity with GAAP shall have been made therefor, 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 Credit Party will file or consent to the filing of any consolidated income tax return, except for any such return of a group of which a Credit Party, Parent Guarantor, a Subsidiary of Parent Guarantor or any Person that directly or indirectly owns Equity Interests in the Borrower as a result of a Permitted Equity Transaction is the common parent.