multiple principals with private types.

VCG contracts and incomplete information. In the VGC contracts of Lavi and Shamash

[22], principal (cid:96)’s payment for an outcome is no longer just her own (reported) value from this

outcome (as in ﬁrst price contracts), but is a function of the other principals’ reported values as

well. In this sense, the payment functions in VCG contracts are reminiscent of payments in VCG
auctions [30, 7, 14].3 Such payments are indeed used in practice – for example, contracts with “price
match guarantee” clauses. Moreover, computerized platforms (such as freelancing platforms) make

VCG contracts easier to coordinate. Such platforms typically have a central intermediary who can

serve as “mechanism designer”. E.g., in online labor markets, the market platform serves as an

intermediary between an agent (freelancer) and the principals who hire him. The platform has
Incomplete Information VCG Contracts for Common Agency