Cal. Rev. & Tax. Code § 19314

(a) Notwithstanding any statute of limitations otherwise provided for in this part, any overpayment due a taxpayer for any year, shall be allowed as an offset in computing any deficiency in tax, for the same or any other year, if the overpayment results from any of the following:
1. (1) A transfer of items of income or deductions or both to or from another year for the same taxpayer.
2. (2) A transfer of items of income or deductions or both for the same year for a related taxpayer described in Section 19110.
3. (3) A transfer of items of income or deductions, or both, to or from another taxpayer for the same or different years if the items of income or deductions are transferred between affiliated taxpayers whose tax is determined under Chapter 17 (commencing with Section 25101) of Part 11.
(b) The offset provided under subdivision (a) shall not be allowed after the expiration of seven years from the due date of the return or returns on which the overpayment is determined.
(c) No refund shall be allowed under subdivision (a) unless before the period set forth in Section 19306 a claim therefor is filed by the taxpayer or unless before the expiration of that period the Franchise Tax Board has allowed a credit or made a refund.