We model a financial market where traders have access both to a fully transparent limit order book (LOB) and to an opaque Dark Pool (DP). When a DP is introduced to a LOB market,orders migrate to the DP from the LOB, but overall trading volume increases. Moreover, inside quoted depth in the LOB...

We build a model of a limit order book and examine the consequences of adding a dark pool. Starting with an illiquid book, we show that book and consolidated ?ll rates and volume increase, but the spread widens, depth declines and welfare deteriorates. When book liquidity increases, more orders...

We show that following a tick size reduction in a decimal public limit order book (PLB) market quality and welfare fall for illiquid but increase for liquid stocks. If a Sub-Penny Venue (SPV) starts competing with a penny-quoting PLB, market quality deteriorates for illiquid, low priced stocks,...

Sub-Penny Trading (SPT) is a form of dark trading that allows traders to undercut displayed liquidity. We distinguish between SPT that is queue jumping (QJ) and mid- crossing (MID) and find that QJ is higher for NASDAQ than NYSE stocks. Consistently with Buti, Rindi, Wen and Werner (2013), QJ is...

This paper examines unique data on dark pool activity for a large cross-section of US stocks in 2009. Dark pool activity is concentrated in large firms, stocks with high share volume, high price, low spreads, high depth, and low short-term volatility. NASDAQ (AMEX) stocks have significantly...

We model a dynamic limit order market with traders that submit orders either to a limit order book (LOB) or to a Dark Pool (DP). We show that there is a positive liquidity externality in the DP, that orders migrate from the LOB to the DP, but that overall trading volume increases when a DP is...

Trading venues often impose a minimum trade unit constraint (MTUC) to facilitate order execution. This paper examines the effects of a natural experiment at Borsa Italiana where the exchange reduced the MTUC to one share for all stocks. After the removal of the MTUC, we observe a substantial...

Reserve orders enable traders to hide a portion of their orders and now appear in most electronic limit order markets. This paper outlines a theory to determine an optimal submission strategy in a limit order book, in which traders choose among limit, market, and reserve orders and...

This paper estimates the effect of employment protection legislation (EPL) on workers' individual wages in a quasi-experimental setting, exploiting a reform that introduced unjust-dismissal costs in Italy for firms below 15 employees and left firing costs unchanged for bigger firms. Accounting...