Form 8594 must also be filed if the purchaser or seller is amending an original or a previously filed supplemental Form. 8594 because of an increase or decrease.Form 8594 is a tax document required in certain business sales where the buyer acquires assets rather than stock or equity. Further, the parties should agree to file a supplemental Form 8594 to reflect any such increase or decrease. 33.3 Buyer and Seller agree to cooperate fully with each other to determine the appropriate asset allocation for this transaction. Enter your name and taxpayer identification number (TIN) at the top of the form. Then check the box for Purchaser or Seller. After completing this form, you should sign the form. You should then file this document with the clerk of the circuit court in the county where the petition.