Space available bonus (also known as "Remnant" space), is a term used by digital out-of-home (OOH) advertising network operators (sellers) to describe un-sold advertising inventory. In the event that advertising space is still available before the start of any given time period, sellers are usually willing to accept a discounted rate vs. letting the space go un-sold. Sometimes, sellers will accept space available bonus contracts in advance, but if another advertiser (buyer) is willing to pay a higher price for the advertising space in question, the space available bonus buyer will get bumped.
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