The TIC report publishes the market value of Japan's holdings, not its trades. When Treasury yields rise, an untouched portfolio is worth less — so part of any fall from the peak is price decline, and part may be real selling. The two effects cannot be separated in this data.
The second caveat is timing: holdings lag the market by roughly 2 months (60 days), so the latest figure (May 1, 2026) describes where the position stood then, not today. What the series does tell you is the size of the position Japan could sell if it chose to defend the yen.
The series itself is the US Treasury's own TIC report: the market value of Japan's holdings, published monthly, shown here over the last ten years. The scale is the point — over a trillion dollars, the largest foreign position in the market everything else is priced off, held as ammunition: if the yen falls too far, Tokyo sells Treasuries and buys yen to defend its currency. Japan also holds over a trillion dollars of US equities, so a broad repatriation would reach the stock market directly, not only through yields.
The two directions mean different things, and neither is as simple as it looks. A fall in this line over a single month can be mostly bond prices moving — but a year is long enough that a real fall means selling, not repricing, and for US equities that is extra Treasury supply pushing yields up while every asset priced off the Treasury curve reprices with them. A rise means the stockpile grew — more ammunition, and a buyer standing where a seller was feared — though the same market-value caveat runs in reverse: falling yields inflate an untouched portfolio too.
For US equities the channel runs through yields: a large forced sale pushes Treasury yields up, and every asset priced off the Treasury curve reprices with them. The trigger — the yen — and the market that would feel it first — the 10-year yield — are tracked on the treasury dump page, and the cost of carrying the debt itself is on the interest costs page.