43 U.S. Code § 375d - Issuance of patent for small tracts; reservations
After the purchaser has paid to the United States all the amount on the purchase price of such land, a patent shall be issued. Such patents shall contain a reservation of a lien for water charges when deemed appropriate by the Secretary, and reservations of coal or other mineral rights to the same extent as patents issued under the homestead laws and also other reservations, limitations, or conditions as now provided by law.
Source(Mar. 31, 1950, ch. 78, § 3,64 Stat. 40.)