The Fed said its holdings of US securities kept for overseas central banks rose $27.14 billion in the week ended November 16, to stand at $3.469 trillion. The breakdown of custody holdings showed overseas central banks' holdings of Treasury debt rose $31.69 billion to stand at $2.750 trillion. Foreign institutions' holdings of securities issued or guaranteed by the biggest US mortgage financing agencies, including Fannie Mae and Freddie Mac, fell by $4.55 billion to stand at $718.7 billion. Overseas central banks, particularly those in Asia, have been huge buyers of US debt in recent years and own more than a quarter of marketable Treasuries. China and Japan are the biggest two foreign holders of Treasuries.