TOKYO - The dollar-yen rate swung sharply over just a few days, with the yen strengthening rapidly from the 159 range to the 153 range, fueling market speculation that Japanese and U.S. authorities may have carried out “rate checks” to signal readiness for intervention.
A rate check is widely seen as the step immediately before actual foreign exchange intervention, typically involving authorities asking financial institutions at what level they can buy or sell dollars and yen, and markets often interpret it as a warning that direct action could follow.
Maruyama, a former Bank of Japan official and now an interest rate and FX strategist at SMBC Nikko Securities, said the yen had been trading in the upper 158 to 159 range following the Bank of Japan’s policy decision and Governor Ueda’s press conference, despite conditions that would normally favor yen strength, before suddenly reversing course. Reports suggested Japan may have conducted a rate check late on Friday, followed by another sharp yen move around 1 a.m. Japan time on Saturday, with speculation that the New York Fed may also have checked rates, raising expectations that intervention could come not only from Japan but potentially from the U.S. side as well.
He said the scale of the move—roughly six yen in about three days—was significant, especially at a time when markets had been focused on concerns over Japan’s fiscal outlook amid political debate over measures such as cutting taxes on food. Those concerns had driven a pattern in which both Japanese government bonds and the yen were being sold, pushing yields higher while weakening the currency, making the sudden reversal more striking.
Maruyama explained that rate checks themselves are normally difficult to confirm, since only the institution contacted would know for sure, and broader speculation tends to spread only after unusual market moves trigger talk among traders and in the media. He added that within the central bank, FX-related operations are tightly controlled and security is high, making it difficult even for insiders to know when actions are being taken.
He said authorities typically avoid confirming whether rate checks have taken place, as refusing to comment can itself deter speculative trading by keeping markets uncertain about how close policymakers are to intervening. If a rate check successfully pushes the exchange rate in the desired direction, authorities may not need to proceed to actual intervention, but if the yen’s move proves insufficient, intervention can follow within as little as one or two days.
Maruyama also noted that speculation about Japan-U.S. coordination would be highly unusual, pointing out that past coordinated interventions generally involved broader G7 action, such as after the 2011 Great East Japan Earthquake, and that there is no clear precedent for confirmed coordination by Japan and the U.S. alone. He suggested the political environment in Washington could be a factor, arguing that a weaker yen can widen the U.S. trade deficit, while a stronger yen may align with U.S. interests, potentially making coordination more plausible than in past administrations.
Source: テレ東BIZ














