From 1994 to 2021, the supply of long-term sovereign debt has increased seven-fold from 2.8 trillion to 18.7 trillion dollars across G10 currency countries. Despite this increase in supply, we find that long-term bond yields have declined over US Treasury auctions. This decline has been strongly integrated across countries and is cumulatively large, 497 basis points for US yields and 452 basis points for G10 yields. These global declines in long-term yields are unique to US Treasury auctions and do not occur over foreign sovereign debt auctions, even those with comparable size. We show evidence that global investors' participation is pivotal for the special role that US Treasury auctions have in revealing persistent and mildly positive shifts in the global demand for long-term bonds.