the dollar amount in effect for such calendar year under section 6041(a) , and (2) in subsection (b)(1)(B), by striking is $5,000 or more and inserting equals or exceeds the dollar amount in effect for such calendar year under section 6041(a) . (d) Application to backup withholding Section 3406(b)(6) is amended— (1) by striking $600 in subparagraph (A) and inserting the dollar amount in effect for such calendar year under section 6041(a) , and (2) by striking only where aggregate for calendar year is $600 or more in the heading and inserting only if in excess of threshold . (e) Conforming amendments (1) The heading of section 6041(a) is amended by striking of $600 or more and inserting exceeding threshold . (2) Section 6041(a) is amended by striking taxable year and inserting calendar year . (f) Effective date The amendments made by this section shall apply with respect to payments made after December 31, 2023. 602. Enforcement provisions with respect to COVID-related employee retention credits (a) Increase in assessable penalty on COVID–ERTC promoters for aiding and abetting understatements of tax liability (1) In general If any COVID–ERTC promoter is subject to penalty under section 6701(a) of the Internal Revenue Code of 1986 with respect to any COVID–ERTC document, notwithstanding paragraphs (1) and (2) of section 6701(b) of such Code, the amount of the penalty imposed under such section 6701(a) shall be the greater of— (A) $200,000 ($10,000, in the case of a natural person), or (B) 75 percent of the gross income derived (or to be derived) by such promoter with respect to the aid, assistance, or advice referred to in section 6701(a)(1) of such Code with respect to such document. (2) No inference Paragraph (1) shall not be construed to create any inference with respect to the proper application of the knowledge requirement of section 6701(a)(3) of the Internal Revenue Code of 1986. (b) Failure to comply with due diligence requirements treated as knowledge for purposes of assessable penalty for aiding and