This paper makes two contributions in the context of seller-buyer relationships with bilateral relationship-specific investment. Firstly, we demonstrate how ex-post negotiations via double auctions can be used to alleviate and often resolve the hold-up problem. Secondly, we show that ex-post participation constraints make the hold-up problem unavoidable in environments where (i)pro duction costs are relatively high compared to valuations and (ii)the trade price is independent of the investment levels.

This paper makes two contributions in the context of seller-buyer relationships with bilateral relationship-specific investment. Firstly, we demonstrate how ex-post negotiations via double auctions can be used to alleviate and often resolve the hold-up problem. Secondly, we show that ex-post participation constraints make the hold-up problem unavoidable in environments where (i) production costs are relatively high compared to valuations and (ii) the trade price is independent of the investment levels.

This paper contributes to the literature on second-price auctions with resale. We add speculators—bidders with value zero—to the standard symmetric independent private values environment. There always exists a continuum of inefficient equilibria that are profitable for a speculator. With no reserve price in the initial auction, specu-lation can enhance the initial seller’s expected revenue. On the other hand, speculation can harm the initial seller even if she commits to an optimal reserve price. Our results are valid for English auctions as well.