25 CFR §169.209

1. (a)We may disapprove an assignment of a right-of-way only if at least one of the following is true:
   1. (1)The Indian landowners have not consented to the assignment under § 169.107 and their consent is required;
   2. (2)Sufficient bonding and/or insurance are not in place;
   3. (3)The grantee is in violation of the right-of-way grant;
   4. (4)The assignee does not agree to be bound by the terms of the right-of-way grant;
   5. (5)The requirements of this subpart have not been met; or
   6. (6)We find a compelling reason to withhold approval in order to protect the best interests of the Indian landowners.
2. (b)We will defer, to the maximum extent possible, to the Indian landowners' determination that the assignment is in their best interest.
3. (c)We may not unreasonably withhold approval of an assignment.