Pennsylvania Statutes Title 72 P.S. Taxation and Fiscal Affairs § 3407-203. Purchaser to pay;  accounting by sellers

The seller shall in each case demand the tax from the purchaser and the purchaser shall pay the same to the seller.  The seller shall keep the amount of all of the taxes so paid to him by all purchasers in a fund separate and apart from the proceeds of the sales and from all his other funds, unless the department otherwise directs.  If the department shall authorize any seller to commingle the proceeds of the tax with the proceeds of sale, the claim of the Commonwealth for the tax shall be enforceable against and shall take precedence over all other claims against the commingled fund.  Each seller shall, as hereinafter provided, account to the Commonwealth for the entire amount of all taxes collected from purchasers.