25 CFR §162.577

1. (a)We may disapprove an assignment of a WSR lease only if at least one of the following is true:
   1. (1)The Indian landowners have not consented and their consent is required;
   2. (2)The lessee's mortgagees or sureties have not consented;
   3. (3)The lessee is in violation of the lease;
   4. (4)The assignee does not agree to be bound by the terms of the lease;
   5. (5)The requirements of this subpart have not been met; or
   6. (6)We find a compelling reason to withhold our approval in order to protect the best interests of the Indian landowners.
2. (b)In making the finding required by paragraph (a)(6) of this section, we may consider whether:
   1. (1)The value of any part of the leased premises not covered by the assignment would be adversely affected; and
   2. (2)If a performance bond is required, the assignee has posted the bond or security and provided supporting documents that demonstrate that:
      1. (i)The lease will be enforceable against the assignee; and
      2. (ii)The assignee will be able to perform its obligations under the lease or assignment.
3. (c)We will defer, to the maximum extent possible, to the Indian landowners' determination that the assignment is in their best interest.
4. (d)We may not unreasonably withhold approval of an assignment.