Using intraday data, we identify the intensity of private information flow in the U.S. Treasury market. Our results show that the intensity of private information flow is highly correlated with public information shocks and higher for longer maturity bonds. More importantly, we find that bond price changes associated with high intensity of private information flow tend to be persistent, whereas those associated with low intensity of private information flow are more likely reversed. While public information and private information are the main determinants of bond price variations on days with news announcements, private information and liquidity shocks are important determinants of bond price variations on days with no significant events. Finally, we show that the depth of limit order book is inversely related to the intensity of private information flow. Nevertheless, informed dealers do not seem to use hidden orders to disguise their trading intentions.

We investigate the impact of scheduled macroeconomic news announcements on the U.S. Treasury market’s efficiency. Using intraday data and controlling for microstructure noise, we employ a robust method to construct market inefficiency measures. We find that the U.S. Treasury market is less efficient in the five-minute interval before news arrival. Our findings are robust for different sample periods, macroeconomic news announcements, and market inefficiency measures. We find that investor heterogeneity provides a possible explanation for the decreased market efficiency before scheduled news announcements.