Section 20.6694-4 - Extension of period of collection when preparer pays 15 percent of a penalty for understatement of taxpayer's liability and certain other procedural matters(a)In general. For rules relating to the extension of the period of collection when a tax return preparer who prepared a return or claim for refund for estate tax under chapter 11 of subtitle B of the Internal Revenue Code pays 15 percent of a penalty for understatement of the taxpayer's liability, and procedural matters relating to the investigation, assessment and collection of the penalties under sections 6694(a) and (b), the rules under § 1.6694-4 of this chapter will apply.(b)Effective/applicability date. This section is applicable to returns and claims for refund filed, and advice provided, after December 31, 2008.T.D. 9436, 73 FR 78451 , Dec. 22, 2008