Form 8594 is a tax document required in certain business sales where the buyer acquires assets rather than stock or equity. Generally, both the purchaser and seller must file Form 8594 and attach it to their income tax returns (Forms 1040, 1041,.Who Must File Form 8594? Both the seller and purchaser of a group of assets that make up a trade or business need to file Form 8594. Both the buyer and seller must complete IRS Form 8594 during the sale to report the sale and purchase of business assets. Learn how to file form 8594 and when to file.