Section 157.6694-1 - Section 6694 penalties applicable to tax return preparer(a)In general. For general definitions regarding section 6694 penalties applicable to preparers of tax returns or claims for refund for tax under section 5891 of the Internal Revenue Code see § 1.6694-1 of this chapter.(b)Effective/applicability date. Paragraph (a) of this section is applicable to returns and claims for refund filed, and advice provided, after December 31, 2008.T.D. 9436, 73 FR 78462, Dec. 22, 2008