The week belonged
to TOPIX breadth

What Moved Tokyo

The week’s closing gains conceal how much work the market did to get there. The Nikkei fell Monday as AI heavyweights dragged on the price-weighted index. It then reversed an intraday drop of more than 900 points on Tuesday, gained 0.62% Wednesday with Advantest doing much of the lifting, slipped Thursday despite strong Nvidia results, and recovered Friday.

TOPIX tells the more important story. It gained in all five sessions and ended Friday with a seventh consecutive advance dating from Aug. 20. Friday’s Prime Market breadth was 873 advancers, 631 decliners and 49 unchanged. That combination points to rotation—toward banks, insurers, autos, domestic demand and selected AI suppliers—rather than a market surviving on one semiconductor stock.

Prime Market turnover reached ¥8.122 trillion Friday. Sixteen of 33 sectors rose and 17 fell, so this was not indiscriminate risk-taking. Shipping, mining and insurance led; other products, precision instruments and pharmaceuticals lagged. Broad participation mattered, but selection still mattered too.

Sector Pulse

The week’s lesson is not that AI stopped mattering. It is that the rest of the market finally had enough weight to keep TOPIX climbing when the Nikkei’s heaviest technology components faltered.

Yen Watch

USD/JPY ended late Friday near ¥160.15, roughly 0.75% above the Aug. 21 close of ¥158.95. The dollar gained after Federal Reserve Chair Kevin Warsh put inflation at the center of his Jackson Hole remarks, pushing markets toward greater odds of a September rate increase.

For Tokyo equities, ¥160 cuts two ways. It can lift translated earnings for automakers, machinery groups and companies with large overseas revenue. It also raises the local price of imported fuel, food and materials, squeezing households and smaller businesses. At this level, verbal warnings from the Ministry of Finance—and the possibility of intervention—become part of routine market pricing.

The Monday question is therefore more precise than “Is a weak yen good for stocks?” It is whether currency support for exporters can offset the U.S. semiconductor selloff and a higher global discount rate.

Rates / JGB Watch

Japan’s 10-year government bond yield finished Friday around 2.93%. A public close table put it at 2.925%, about 5.5 basis points above the Japan Bond Trading Co. official Aug. 21 close of 2.870%. Domestic inflation data and expectations of further BOJ normalization met a parallel rise in global yields.

The U.S. 10-year yield ended near 4.71%, while the two-year yield jumped more sharply after Warsh spoke. That steep repricing complicates the handoff to Tokyo: banks and insurers may welcome better reinvestment economics, but property, utilities and long-duration technology carry higher financing and valuation costs.

A JGB yield near 3% is not merely a trading screen milestone. Its eventual path runs through mortgages, corporate bonds and capital spending. The same rate move can improve a megabank’s outlook while worsening the budget of a leveraged small company.

Global Handoff

The information arriving after Friday’s Tokyo close was less supportive than the local finish. The S&P 500 lost 0.25%, the Nasdaq Composite fell 0.52% and the Dow was nearly flat. Nvidia dropped 4.6% and Marvell Technology 10.3%, leaving Japan’s chip equipment and component makers with a negative U.S. lead for Monday. The weekly U.S. result remained positive: about 0.5% for the S&P 500 and 0.8% for the Nasdaq.

Europe’s STOXX 600 added 0.51% to 655.16 on Friday as autos, luxury shares and banks advanced. At the same time, higher Treasury yields, a stronger dollar and a roughly 3% fall in gold showed that investors were repricing the path of policy, not simply buying risk everywhere.

Monday’s Tokyo open must reconcile two opposing impulses. Yen weakness can cushion Japanese exporters, but a U.S. chip pullback and higher yields directly challenge the part of the Nikkei that drove its midweek rebounds. Friday’s Tokyo close is final; the global message that followed it is newer.

Policy / BOJ Watch

Tokyo’s core consumer-price index, excluding fresh food, rose 1.8% from a year earlier in August, its third consecutive acceleration. The measure excluding both fresh food and energy gained 2.0%. Japan’s seasonally adjusted unemployment rate fell 0.1 percentage point to 2.4% in July, leaving the BOJ with a firm labor backdrop and an inflation picture that still requires attention.

Deputy Governor Ryozo Himino said Thursday that the Bank should continue adjusting the degree of monetary accommodation if activity, prices and financial conditions evolve as projected. He also said inflation could run above 2% in the second half of fiscal 2026. That is a conditional policy path, not a promise to raise rates in September; Himino explicitly identified the Middle East, AI demand and foreign exchange as risks to monitor.

The next Monetary Policy Meeting is scheduled for Sept. 17–18. Before then, comments around the G20 gathering—from Finance Minister Satsuki Katayama, BOJ Governor Kazuo Ueda and their counterparts—will be watched closely as the yen hovers near ¥160. Currency policy and monetary policy are becoming harder for the market to price separately.

Publisher’s Market Note

The week’s most useful number was not 66,405.56. It was the performance gap between TOPIX and the Nikkei. A tape dominated by noisy chip headlines still found buyers elsewhere, and that is healthier than one-stock leadership. But the breadth came with a ¥160 dollar and a JGB yield near 3%—real costs for households and small firms. Stronger market plumbing is worth noting; it should not be confused with universally stronger living conditions.

Before the Next Open

• The ¥160 line: Watch Ministry of Finance and BOJ comments, including around the G20, for intervention sensitivity.
• The semiconductor handoff: Can yen support offset Friday’s declines in Nvidia and Marvell for Japan’s chip complex?
• Two bond markets: A 10-year JGB near 2.93% and a U.S. 10-year near 4.71% favor financials but raise the hurdle for rate-sensitive growth and property.
• Breadth under pressure: If Nikkei-heavy chip shares weaken, do banks, insurers, autos and domestic-demand names preserve TOPIX’s seven-session advance?
• U.S. payrolls later in the week: August employment data could further shift expectations for the Fed’s September decision.

Sources and Method

This report uses public information only and separates confirmed Tokyo closes from late New York currency quotes and public bond-closing tables. Japan.co.jp calculated weekly changes from Aug. 21 to Aug. 28. Delayed feeds and later corrections can change source displays. No paywalled article text was copied. This is independent Japan.co.jp market reporting and not investment advice.

• Nikkei Inc. — official Nikkei 225 historical data
• Japan Exchange Group — TOPIX / Yahoo! Finance Japan — TOPIX history
• Reuters — Aug. 28 Tokyo market close
• Bank of Japan — Deputy Governor Himino speech / Statistics Bureau — Tokyo CPI / Labour Force Survey
• Reuters — Aug. 28 U.S. market close / Reuters — foreign-exchange close