25 USC 993 - Claims

(a) Time for filing; reversion of funds upon failure to file 
All claims for per capita shares, whether by a living enrollee or by the heirs or legatees of a deceased enrollee, shall be filed with the Area Director of the Bureau of Indian Affairs, Muskogee, Oklahoma, not later than three years from October 9, 1962. Thereafter, all claims and the right to file same shall be forever barred and the unclaimed shares shall revert to the tribe.
(b) Use of reverted funds 
Tribal funds that revert to the tribe pursuant to this subchapter, including interest and income therefrom, may be advanced or expended for any purpose that is authorized by the principal chief of the Cherokee Nation and approved by the Secretary of the Interior.