20.6694-2—Penalties for understatement due to an unreasonable position.
        
        (a) In general.
         A person who is a tax return preparer of any return or claim for refund of estate tax under chapter 11 of subtitle B of the Internal Revenue Code (Code) shall be subject to penalties under  section 6694(a) of the Code in the manner stated in  § 1.6694-2 of this chapter.
    
    
        
        (b) Effective/applicability date.
         This section is applicable to returns and claims for refund filed, and advice provided, after December 31, 2008.