W.S. § 39-17-310 — Statute of limitations

(a) The refund form and receipts, as provided for in W.S.
39-17-309 are invalid if not submitted to the department within
one (1) year following date of purchase or eighteen (18) months
for agricultural producers seeking refunds.
(b) Each supplier, refiner, terminal operator, importer,
exporter, distributor and dealer shall keep and preserve the
records relating to the purchase and sale of alternative fuels
for not less than three (3) years. The department may authorize,
by rule, alternate methods of preserving records required under
this section.