This article explores the effect of a subset of symmetric bidders joining to bid together. Possible applications include mergers, collusion and joint-bidding arrangements. The change produces a “strong” party with a more advantageous value distribution than the remaining “weak”...

We study, theoretically and experimentally, sealed-bid first-price auctions with and without package bidding. In the model, a global bidder bids for multiple items and can benefit from synergies, while local bidders bid for a single item. In the equilibrium, package bidding improves (hurts)...