Counterparty risk could hamper trade and worsen a financial crisis. A central clearing party (CCP) insures traders against counterparty default and thus benefits trade. Default of the CCP however becomes a new systemic risk. CCP risk management does not account for risks associated with crowded positions. This paper proposes a CCP exposure measure based on tail risk in trader portfolios. It identifies and measures crowded risk and assigns it to traders according to the polluter pays principle. CCP data show that crowded positions increase CCP exposure most (about one-third) on turbulent days, when exposure is high already.

A faster exchange does not necessarily improve liquidity. On the one hand, speed enables a high-frequency market maker (HFM) to update quotes faster on incoming news. This reduces payoff risk and thus lowers the competitive bid-ask spread. On the other hand, HFM price quotes are more likely to meet speculative high-frequency bandits, and thus are less likely to meet liquidity traders. This raises the spread. The net effect of exchange speed depends on a security's news-to-liquidity-trader ratio.

A faster exchange does not necessarily improve liquidity. On the one hand, speed enables a high-frequency market maker (HFM) to update quotes faster on incoming news. This reduces payoff risk and thus lowers the competitive bid-ask spread. On the other hand, HFM price quotes are more likely to meet speculative high-frequency bandits, and thus are less likely to meet liquidity traders. This raises the spread. The net effect of exchange speed depends on a security's news-to-liquidity-trader ratio.

We characterize the dynamic fragmentation of U.S. equity markets using a unique data set that disaggregates dark transactions by venue types. The “pecking order” hypothesis of trading venues states that investors “sort” various venue types, putting low-cost-low-immediacy venues on top and high-cost-high-immediacy venues at the bottom. Hence, midpoint dark pools on top, non-midpoint dark pools in the middle, and lit markets at the bottom. As predicted, following VIX shocks, macroeconomic news, and firms’ earnings surprises, changes in venue market shares become progressively more positive (or less negative) down the pecking order. We further document heterogeneity across dark venue types and stock size groups.