Securing All Livestock Equitably Act of 2017 or the SALE Act of 2017 This bill amends the Packers and Stockyards Act, 1921 to require all livestock purchased by a dealer in cash sales and all inventories of, or receivables or proceeds from, such livestock to be held by the dealer in a trust until all unpaid cash sellers of the livestock have been paid. The bill exempts from the requirement any dealer whose average annual purchases of livestock do not exceed $500,000.