Rev. & Tax. Code, § 24943

If property (as a result of its destruction in whole or in part, theft, seizure, or requisition or condemnation or threat or imminence thereof) is compulsorily or involuntarily converted—

(a) Into property similar or related in service or use to the property so converted, no gain shall be recognized.

(b) Into money, and the disposition of the converted property occurred before January 1, 1953, no gain shall be recognized if such money is forthwith in good faith, under regulations prescribed by the Franchise Tax Board, expended in the acquisition of other property similar or related in service or use to the property so converted, or in the acquisition of control of a corporation owning such other property, or in the establishment of a replacement fund. If any part of the money is not so expended, the gain shall be recognized to the extent of the money which is not so expended (regardless of whether such money is received in one or more taxable years and regardless of whether or not the money which is not so expended constitutes gain). For purposes of this subsection and Section 24944, the term “disposition of the converted property” means the destruction, theft, seizure, requisition, or condemnation of the converted property, or the sale or exchange of such property under threat or imminence of requisition or condemnation.

For purposes of this section and Section 24944, the term “control” means the ownership of stock possessing at least 80 percent of the total combined voting power of all classes of stock entitled to vote and at least 80 percent of the total number of shares of all other classes of stock of the corporation.