Generally, both the purchaser and seller must file Form 8594 and attach it to their income tax returns (Forms 1040, 1041,. Form 8594 is a tax document required in certain business sales where the buyer acquires assets rather than stock or equity.IRS Form 8594 defines seven asset classes to which the entire purchase price must be allocated. Need to disclose asset allocations. Most tax returns have a special form to disclose the allocation and valuation of asset sales.