Cal. Rev. & Tax. Code § 19355

Any action of the Franchise Tax Board in refunding the excess of tax withheld under Section 18662 or 18666 or estimated tax paid pursuant to Section 19136 or any action of the Employment Development Department in refunding to the employer the excess tax withheld under Section 13020 of the Unemployment Insurance Code shall not constitute a determination of the correctness of the return of the taxpayer for purposes of this part.