Elastic in cash, inelastic in repo: hedge funds in the treasury and repo markets

The functioning of sovereign bond markets is closely intertwined with repo markets, where investors finance long positions and source bonds for short sales. We show, theoretically and empirically, how conditions in the cash bond market fundamentally shape repo rates: When demand for cash bonds exceeds available supply, arbitrageurs, notably hedge funds, step in to bridge the gap by shorting bonds and borrowing them in the repo market. These arbitrage strategies drive a wedge between monetary pol