California Code, Revenue and Taxation Code - RTC § 19753

(a) This article does not apply to violations of this part for which, as of December 31, 2003, any of the following applies:

(b) No refund or credit shall be granted with respect to any penalty paid prior to the time the taxpayer participates in the voluntary compliance initiative authorized by this article.

(c) For purposes of this article, an “abusive tax avoidance transaction” means a plan or arrangement devised for the principal purpose of avoiding tax. Abusive tax avoidance transactions include, but are not limited to, “listed transactions” as described in paragraph (4) of subdivision (a) of Section 18407.