LIABILITY OF PRODUCER AND PURCHASER.
Tex. TAX Code § 202.251.
in effectThe tax imposed by this chapter is the primary liability of the producer and is a liability of the first purchaser and each subsequent purchaser. Failure of the first purchaser to pay the tax does not relieve the producer or a subsequent purchaser from liability for the tax. A purchaser of oil produced in the state shall satisfy himself that the tax on that oil has been or will be paid by the person liable for the tax.
