We study the equilibrium implications of a multi-asset economy in which asset managers performance is tied to different benchmarks, reflecting heterogeneity in their investment mandates. Fluctuations in the capital asset managers invest for benchmarking purposes, scaled by the size of the economy, induce price pressure that results in negative spillovers across assets. We characterize a rich structure of asset price comovement within and across benchmarks by analyzing shock elasticities and cross-elasticities of price-dividend ratios. Evidence on the heterogeneity of mutual fund mandates and the benchmarking-induced return comovement across cap-style and industry-sector portfolios corroborates the model assumptions and predictions.

Real‐world contracts are typically private, observed only by their direct signatories, so agents working together are vulnerable to the principal opportunistically reducing other agents' incentives. The principal can mitigate this commitment problem by giving the most skilled agent a budget and delegating authority to write other agents' contracts. This endogenous hierarchy, never optimal with public contracts, raises effort, output, and compensation but allows rent extraction. The principal prefers it when contracts are opaque enough, skill is sufficiently heterogeneous across agents, and joint output is sensitive enough to effort. Our model provides novel predictions for the structure of banking syndicates.