These are Tax Preparers' Due Diligence Requirements as stated on the IRS Web site:

The Taxpayer Relief Act of 1997 enacted a law concerning the EITC and preparers' due diligence in determining their client's eligibility for the credit and the credit amount. Paid preparers who file EITC returns or claims for refunds for their clients must meet four due-diligence requirements. Those who fail to do so can be assessed a $100 penalty for each failure. Section 6695(g) of the Internal Revenue Code governs the application.

Here are the four due diligence requirements you must meet:

1. You must complete Form 8867, Paid Preparer's Earned Income Credit Checklist, or complete your own form as long as it provides the same information.

2. You must complete the appropriate EIC worksheet found in the Form 1040 instructions or in Publication 596, or complete your own worksheet as long as it provides the same information.

3. You must have no knowledge that any of the information used to determine the taxpayer's eligibility for the credit and the credit amount is incorrect.

4. You must keep Form 8867 and the EIC worksheet (or your own equivalents of each) and a record of how, when, and from whom the information used to prepare the form and worksheet was obtained. You must keep these documents for three years from June 30th following the date the return or claim for refund was presented to the taxpayer.

To watch IRS-produced videos regarding due diligence, see the IRS Web site: https://www.eitc.irs.gov/