43 CFR § 3135.1-4
Effect of transfer of a tract
June 11, 2020
(a) When a transfer is made of all the record title to a portion of the acreage in a lease, the transferred and retained portions are divided into separate and distinct leases. The BLM will not approve transfers of a tract of land:
(1) Of less than 640 acres that is not compact; or
(2) That would leave a retained tract of less than 640 acres.
(b) Each segregated lease shall continue in full force and effect for the primary term of the original lease and so long thereafter as the activities on the segregated lease support extension in accordance with §3135.1-5.
[73 FR 6442, Feb. 4, 2008]