We solve a flexible model that captures transactions costs and infrequencies of trading opportunities for illiquid assets to better understand the shadow costs of illiquidity for different origins of asset illiquidity and heterogeneous investor types. We show that illiquidity that results in suboptimal asset allocation carries low shadow costs, whereas these costs are high when illiquidity restricts consumption. As a result, the shadow costs are high for short-term investors, investors who face substantial liquidity shocks, and investors who desire to allocate a large fraction of their wealth to illiquid assets.

Defined benefit pension funds invest in illiquid asset classes for return, diversification or liability hedging reasons. So far, little is known about factors influencing how much they invest in illiquid assets. We conjecture that liquidity and capital requirements are pivotal in this decision. Short-term pension payments and margining on derivative contracts generate liquidity requirements, while regulations impose capital requirements. Consistent with our model we empirically find that these requirements create a hump-shaped impact of liability duration on the fraction of risky assets invested in illiquid assets. Further, we report that pension fund size, type, and funding ratio impact illiquid assets allocations.