43 U.S.C. § 1166 : Public Lands — Miscellaneous Provisions Relating To Public Lands — Disposition Of Suspended Entries And Claims; InValid And Defective Claims And Patents Therefor — Limitations Of Suits To Annul Patents Date: 9 Feb 2017 TEXT PDF Suits by the United States to vacate and annul any patent shall only be brought within six years after the date of the issuance of such patents. (Mar. 3, 1891, ch. 559, 26 Stat. 1093; Mar. 3, 1891, ch. 561, § 8, 26 Stat. 1099.)