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. Go to Screen 65, Asset Acquisition Statement (8594) (Screen 58 for S-Corp). Learn how to file form 8594 and when to file.