Arbitrage traders are leveraging Japan's "market rescue" efforts to rebuild their short positions on the yen, with USD/JPY potentially testing the 162 level again.

The effectiveness of Japanese authorities’ foreign exchange market intervention to prop up the yen is coming under growing challenge. Market data indicates that carry traders are capitalizing on every yen rebound to re-establish short positions, forming a cycle of “intervention lifts the yen — traders sell on the rise”. Earlier, the joint U.S.-Japan intervention briefly pushed the yen higher, but less than two weeks later, USD/JPY once again neared 160. For carry traders, official intervention instead provides a more favorable yen selling price. This trading logic hinges primarily on interest rate spread advantages: investors borrow low-yield yen to allocate to high-yield assets; as long as the yen does not sustain appreciation, the interest rate differential can offset part of the exchange rate risk. As of August 4, hedge funds’ yen short positions have shrunk by roughly half, yet some institutions are re-establishing carry trades funded by the yen. Market data shows USD/JPY has rebounded from near 157 to 159.43. Some traders argue that without a significant decline in the U.S. dollar and U.S. yields, carry trades could push USD/JPY to retest 162. Japanese authorities were previously reported to have deployed tens of billions of dollars to support the yen at the end of July, with a single-day intervention hitting around $53 billion — a historical record. But the massive intervention still failed to prevent the yen from approaching 160 again, reflecting that the market’s focus on the U.S.-Japan interest rate differential and Japan’s fiscal pressure remains dominant. Currently, the market is closely watching the Bank of Japan’s (BOJ) next policy move. Traders are betting the BOJ may raise rates by 25 basis points in September or October, but analysts note that as long as Japan’s interest rates stay significantly lower than those of major economies like the U.S., yen-funded carry trades are likely to persist.