We analyze the effects of mergers and the introduction of concurrent marketing mechanisms on the seller’s revenue, price trend and efficiency in sequential auctions under complete information with asymmetric bidders. First, we provide conditions for bidders to be strategic when the number of objects is less or greater than the number of bidders as this impacts upon the set of possible mergers. Second, we show that mergers may simultaneously increase the seller’s revenue and improve efficiency. Third, we show that having a marketing mechanism working alongside the auction can increase or decrease the average auction price. We use weekly data about Quebec’s daily hog auction to ascertain the effects of a merger and of changes in the weights of concurrent marketing mechanisms on daily auction prices. Our empirical analysis relies on an endogenous structural change test which detected three breaks corresponding to: i) the introduction of a new concurrent mechanism, ii) a joint-venture partnership of the two largest hog processing firms and iii) an announcement by Canada’s Competition Bureau authorizing the full merger of the same two firms.