The Japanese Yen has appreciated by approximately 4% against the US Dollar this month, briefly touching the 153 level and breaking below the key support level of 155. Data from the Chicago Mercantile Exchange shows hedge funds are actively positioning in call options, with some betting on USD/JPY falling below 150 or even as low as 140 this year. The total volume of put options expiring this year is more than three times that of call options. Meanwhile, Japanese retail investors have bucked the trend by increasing their short positions in the Yen, with net short positions totaling approximately JPY 3.61 trillion (about USD 23.5 billion) last week, an increase from August. Mizuho Bank warned that if the Yen continues to appreciate, retail investors might be forced to close their long USD positions, triggering additional selling.

The recent appreciation of the Yen is driven by hawkish statements from Bank of Japan (BOJ) Governor Kazuo Ueda and board member Hajime Takata, as well as market expectations that domestic pension funds may adjust their asset allocations. According to Bloomberg, the BOJ is leaning towards a 25 basis point rate hike this month to address inflation pressures. US Treasury Secretary Scott Bessent publicly addressed traders on Tuesday, stating he is "the house now," implying US support for Yen appreciation, which further bolstered market confidence in long Yen positions.