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. The purpose of Form 8594 is to determine the treatment of the assets for tax purposes, establish the basis of the acquired assets for the purchaser. You can use these forms and instructions to file City tax returns. Form 8594 is the Asset Acquisition Statement, which the buyer and seller must complete and submit to the IRS. Forms and instructions to use when filing City tax returns. Forms include supplementary schedules and worksheets from 2009 to present.