Wyo. Stat. § 36-9-114
In case any person, persons or corporation shall pay to the board of land commissioners any money for any state or school lands sold to him, or them, or in case any person shall pay into the state treasury, any money in consideration of the leasing of lands, which said board supposed to belong to the state, and it shall thereafter be discovered that such lands do not belong to the state, and were not subject to sale by the state, as state or school lands, such money, together with interest-except in the case of money paid for leases-at the rate of six percent (6%) per annum from the date of the patent for such lands, but without interest if they have not been patented, shall be refunded to the person buying the same, upon certificate from the board of land commissioners to the effect that such money has been paid under mistake as aforesaid, such certificate being accompanied by a verified statement of account thereof, as in the case of other claims against the state; and upon the presentation of such certificate to the state auditor he shall draw his warrant upon the state treasurer for the amount named in such certificate, if the same is within the limit of any appropriation of money for said purpose. And it is hereby made the duty of said board to furnish such certificates upon ascertaining the fact of the mistake having been made.
W.S. 36-9-114