Upon service of the notice and claim of lien, the owner may retain, out of the amount due or to become due the original contractor, the value of the labor or material furnished as shown by the notice and claim of lien. The owner shall furnish the original contractor with a true copy of the notice and claim of lien and if the contractor does not, within ten days after receipt of the copy, give the owner written notice that he intends to dispute the claim, he shall be considered as assenting to the demand, which shall be paid by the owner when it becomes due.