Japanese government bond yields have risen notably in early July 2025, with the 30-year bond yield increasing by approximately 20 basis points over three days to around 3.09%–3.10%, nearing record highs. The 40-year bond yield also surged by about 30 basis points to approximately 3.36%, close to its highest level since its introduction in 2007. The 20-year and 5-year yields have similarly edged higher, with the 20-year yield reaching around 2.475% and the 5-year yield near 0.975%. This upward movement in yields reflects increased market volatility and has implications for risk assets and borrowing costs. Concurrently, Japanese investors purchased the most US sovereign bonds since August 2024 in May, indicating active cross-border bond market activity. The rise in Japanese bond yields occurs alongside elevated US Treasury yields, with the 30-year US Treasury yield approaching the 5.0% mark again. These developments are occurring amid broader global bond market jitters, including high UK 30-year yields at 5.45%. The increase in long-term yields in both Japan and the US is notable given the record debt levels in these economies and may signal rising borrowing costs and potential pressure on growth-sensitive assets.