Multiple Unit Auctions and Short Squeezes

This article develops a theory of multiunit auctions where shortsqueezes can occur in the secondary market. Both uniform anddiscriminatory auctions are studied and bidders can submit multiplebids. We show that bidders with short and long preauction positionshave different valuations in an otherwise common value setting.Discriminatory auctions lead to more short squeezing and higherrevenue than uniform auctions, ceteris paribus. Asymptotically,as the auction size approaches infinity, the two formats leadto equivalent outcomes. Shorts employ more aggressive equilibriumbidding strategies. Most longs strategically choose to be passive.Free riding on a squeeze by small, long players has no impacton these results, but affects revenue in discriminatory auctions.