43 U.S.C. § 6 — Duties of employees to certify, record, etc., patents

The Secretary of the Interior designates certain officers or employees of the Bureau of Land Management for this job, and those designated people — following instructions from the Secretary or from an officer the Secretary picks — must certify every patent for public lands and affix the office's seal to it. They're also responsible for making sure those patents are correctly written out in final form, correctly recorded, and correctly sent onward. On top of that, they must prepare alphabetical indexes listing the names of patentees (people who received patents) and people who are entitled to receive one. And they must prepare copies and certified exemplifications of material on file or recorded at the Bureau of Land Management, whenever the Secretary or the designated officer directs them to.