Japan's Ministry of Finance (MOF) said on Monday it intervened three times this summer to support the yen, confirming earlier reports including a nearly 30-year-first joint action with the United States. MOF's quarterly daily FX intervention data showed the operations spanned three days, surprising traders who had expected two. On July 30 authorities bought a record JPY 7.98 trillion (~$50.4 billion) of yen; purchases on the following days were JPY 5.55 trillion and JPY 1.87 trillion.