Oregon Revised Statutes Animals § 599.520

(1) No person shall make any by-bids or other false or fraudulent bids designed to stimulate bona fide bidding at any auction sale of livestock.

(2) No person shall conspire with any other person for the purpose of making such a bid or make any false statement relative to any such livestock being sold, with intent to deceive any bidder or with intent to influence any bid therefor. Any false statement relative to such livestock, made by the owner thereof or the agent of the owner, shall prima facie be presumed to have been made with intent to deceive any such bidder.

(3) However, this section does not prohibit the owner or consignor of livestock offered at public auction from announcing a minimum or reserve bid, which shall either be noted in the catalog of such auction or announced by the auctioneer.