Did Japan Sell Treasuries Today?

Bonds sold off medium big on Friday in a move that offered little by way of overt explanations. There were reports of "rate checks" in the USD/JPY market--something that CAN precede the selling of U.S. bonds in order to buy JPY. Notably, there were no reports of actual intervention, but sometimes these things aren't revealed until the following trading day. If this explains today's weakness (and to be clear, we're not sure it does), it would be good for the U.S. bond market as it would mean 10yr yields still held under 5% despite added, artificial pressure. Causality investigations aside, we'd focus on the fact that 10yr yields held under 5% (albeit just barely), which is right where they were on the Tuesday afternoon before Fed day.