Form 2439: Notice of Undistributed Long-Term Capital Gains to Shareholder What is a 3800 form? The 3800 form is an IRS form used to claim the general business credit. The form is used to figure the credit carryforward to future tax years, and to figure any recapture of the credit. What is a form 6252? A form 6252 is an IRS form used to calculate the installment sale income from the sale of certain property. What is Schedule H IRS? The Schedule H IRS is a form that is used to report certain types of household employment taxes. This includes taxes such as Social Security and Medicare. Who must file Form 6252? You must file Form 6252 if you have income from an installment sale. Do I need to file form 2439? Yes, you need to file form 2439 if you have received certain types of income that are subject to backup withholding. This includes interest, dividends, and capital gains.