Further, the parties should agree to file a supplemental Form 8594 to reflect any such increase or decrease. 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. Both entities must submit IRS Form 8594 with matching allocations. Such alignment reduces audit risk. Form 8594 is a tax document required in certain business sales where the buyer acquires assets rather than stock or equity. The form serves as a record for the IRS, detailing how the purchase price is allocated among various assets to reflect their fair market value.