NextFin News - Natixis Investment Managers has raised its allocation to Japanese equities and cut exposure to US stocks, a shift that places the Paris-based asset manager firmly on one side of the broadest global portfolio rotation in years. The decision, disclosed this week, rests on a divergence that has widened through 2026: Japanese shares have returned 22.9% this year in local currency while the S&P 500 has gained 13.2% in dollar terms, and Tokyo still trades at a material discount to Wall Street despite the gap in performance.
The move is not a simple performance chase. It is a structural bet that the engine behind Japan's rally - a corporate-governance overhaul enforced by the Tokyo Stock Exchange, record buybacks, and a broadening base of earnings winners - is durable, while the engine behind US leadership is narrowing. Seven companies now account for roughly a third of the S&P 500's market value. Natixis's strategists see that concentration as the risk to reduce, not the anchor to hold.
The Performance Gap That Made the Rotation Inevitable
The arithmetic behind the allocation change is unforgiving. Since the start of the year, the Topix has posted a 22.9% gain in local currency including dividends - or 21.2% in US dollars - while its US counterpart, the S&P 500, has risen by only 13.2% in dollar terms, according to Natixis Investment Managers' market strategy team. That outperformance held even as the yen weakened, which should, in theory, have flattered dollar-hedged US returns rather than Japanese ones.
Romain Aumond, senior macroeconomist and quantitative strategist at Natixis Investment Managers, and Mabrouk Chetouane, head of global market strategy, frame the divergence as a matter of balance rather than momentum: "A balance between growth drivers has been key to the success of Japanese equities since the beginning of the year."
The balance they describe is not the familiar weak-yen export story that defined Japan's equity market for a generation. It is a domestic balance-sheet story, and it shows up in the flow data. Overseas investors purchased a net 9.7 trillion yen, or more than $60 billion, of Japanese stocks in the first half of 2026 - the largest half-year total on record, surpassing the previous high set during the first half of 2013, when stimulus-era policies drove the market higher, according to Tokyo Stock Exchange data. Foreign ownership of Japanese equities reached a record for the third consecutive year in fiscal 2025, with overseas investors now holding more than one-third of the domestic market, heaviest in AI-related companies and names held by activist funds.
That flow is the market's answer to a policy question. The Tokyo Stock Exchange's pressure on companies trading below book value has forced a change in corporate behavior that is now visible in the data: the share of Topix constituents with a price-to-book ratio below one has fallen from 51% at the end of 2022 to 38% by the end of June 2026, according to Daiwa Asset Management. Buybacks and dividends have risen in tandem. Natixis writes that the governance transformation "which began a few years ago and is now yielding results - is leading to an increase in share buybacks and higher dividend payouts, while also supporting efforts to improve RoE."
That is the transmission mechanism, stated plainly: a regulator with listing-rule leverage changes the cost-of-capital discipline facing corporate boards; boards respond by returning cash and lifting return on equity; foreign investors, who spent a decade treating Japan as a value trap, re-rate the index. The mechanism is self-reinforcing because higher share prices lift price-to-book ratios, which reduces the number of companies under regulatory pressure - which is exactly what the decline from 51% to 38% of firms below book value shows.
Why the US Side of the Trade Is Getting Cut
The other half of Natixis's move is a judgment about what US market leadership now costs. The S&P 500's 13.2% year-to-date gain is real, but it is narrow. The seven largest technology companies - Nvidia, Microsoft, Apple, Alphabet, Amazon, Meta Platforms and Tesla - make up roughly 34% of the index's market value, according to index data compiled in mid-2026. From 2023 through 2025, that concentration did the heavy lifting: the capitalization-weighted S&P 500 gained 68.4%, while the equal-weighted index gained 34.2%, about half as much.
Natixis's house view remains "prudently positive" on US equities, with earnings growth of 10% to 15% and buybacks providing support. But the firm's strategists have flagged the concentration in artificial-intelligence-related winners as a reason for selectivity rather than broad exposure. Karen Kharmandarian, chief investment officer of thematic equities at Mirova, a Natixis Investment Managers affiliate, put the rotation in blunt terms: the so-called Magnificent Seven "have underperformed this year while there has been significant performance in South Korea, Japan and Europe. Less so from the US."
The concentration risk is not merely a valuation concern; it is a correlation risk. When one theme drives one-third of an index, a disappointment in that theme becomes a market-level event rather than a sector event. Natixis's cut to US exposure is, in that sense, a diversification trade first and a valuation trade second. Daniel Nicholas, a client portfolio manager at Harris Oakmark, another Natixis Investment Managers affiliate, has said his firm is "significantly underweight in US equities, in favor of Europe," citing the same concentration problem: "In the US, because of the concentration of US stocks, it's also a wonderful time to diversify US exposure."
Nicholas added a political-economy dimension to the shift that helps explain why the rotation has been so sharp: "Last year, the US was the only game in town, with US exceptionalism prevailing. Every economist was overweight in the US. Then came so-called Liberation Day and that all changed and the war in Iran as well."
The Counter-Argument: US Earnings Power Is Not an Illusion
The strongest case against Natixis's rotation is that US market dominance is earned, not accidental. Goldman Sachs Research has argued that the 2026 US rally has been powered entirely by corporate profit growth rather than multiple expansion, and that the dynamic should continue into 2027. Under that reading, trimming the US because it is concentrated is like trimming a portfolio because its winners won. The earnings math is real: US companies are generating the profits, the cash flow, and the global revenue growth that justify their weights.
There is also a timing risk on the Japan side. Japanese equities have now risen more than 20% for four consecutive years since 2023, a cumulative 136% move from the start of 2023, according to Daiwa Asset Management. Momentum that persistent invites a mean-reversion trade. The yen remains weak - the dollar traded near 159 in mid-August - and a sharper-than-expected reversal in USD/JPY could compress the dollar returns of unhedged Japanese holdings just as the allocation is being raised. Higher Japanese interest rates also raise the domestic cost of capital, which weighs on equity valuations; the Bank of Japan's policy rate stood at 1.00% as of July, and the 10-year government bond yield has been climbing.
Natixis's answer, embedded in its research, is that Japan's rally is differently constructed from the US one. It is broader across sectors, cheaper on forward earnings - the Topix trades at roughly 15.5 to 16 times forward earnings versus more than 21 times for the S&P 500, depending on the estimator - and backed by a governance reform that will not be repealed when the next earnings cycle turns. The US concentration, by contrast, is a bet on a single technological trajectory continuing to compound without interruption.
The ROE Threshold: The Signal That Would Prove the Rotation Wrong
The rotation thesis stands or falls on one observable condition: whether the Topix's return on equity can stay above the 8% threshold at which price-to-book expansion historically accelerates, according to Daiwa Asset Management's analysis of two decades of monthly data. When the Topix's ROE is 8% or lower, the correlation with price-to-book is weak; once it exceeds 8%, PBR tends to rise in tandem. Consensus forecasts project that the Topix ROE will exceed 10% in fiscal 2026 and continue rising through fiscal 2027.
If Topix ROE slips back below 8% while buyback growth stalls, the governance-reform narrative loses its earnings anchor and the Japan overweight becomes a momentum position without fundamentals. That is the single falsifying signal for the structural call. On the buyback front, the evidence currently runs the other way: Japanese companies have flagged more than 6.5 trillion yen of buybacks since April 1, on pace for a record fiscal year, according to buyback data compiled from company announcements, and total shareholder returns - buybacks plus dividends - exceeded 45 trillion yen in the past fiscal year, including a record 21.7 trillion yen in dividends.
On the US side, the falsifying signal runs in the opposite direction. If the Magnificent Seven's share of S&P 500 earnings rises alongside their market weight - rather than diverging from it - then the concentration is justified by cash generation and the "diversify away from the US" trade is the one that will underperform. A sustained rebound in US small-cap earnings growth, which has lagged large caps through 2026, would point to the same conclusion: breadth returning to America, not Japan.
Outlook: Three Horizons, Three Different Trades
Short term (sentiment and flows): The allocation shift itself is a flow catalyst. Passive and active money that has been underweight Japan now has permission to chase a 22.9% year-to-date rally, which paradoxically increases the risk of a near-term pullback on overbought positioning. Expect volatility to rise, not fall, as the rotation accelerates. The Topix traded near 4,150 to 4,180 around the turn of September, below the record intraday high of 72,831 on the Nikkei 225 in late June, leaving room for both a momentum continuation and a sharp reversal.
Medium term (fundamentals): The base case is continued Japanese outperformance on earnings breadth and shareholder-return growth, with the Topix reaching the 4,500 level that Goldman Sachs Research has targeted over the next 12 months - up from around 3,960 in early August, a gain of roughly 14%. The upside case is a faster re-rating if ROE clears 10% and the share of companies below book value keeps falling toward historical norms; Daiwa Asset Management forecasts the Nikkei 225 at 79,000 by the end of 2026 and 86,000 by the end of 2027. The downside case is a yen-driven earnings squeeze for exporters if USD/JPY falls sharply; Citi has estimated the dollar could trade near 163 if the Topix reaches 4,500, implying the equity move and the currency move are intertwined rather than independent.
Long term (structure): This is where the structural call matters most. If Japan's governance reform is a regime change, the country's discount to global peers - a gap of 14% to 27% on forward P/E multiples depending on the estimator - should close gradually over years, not quarters. If it is a cyclical re-rating, the discount will reopen once the buyback cycle peaks. Natixis is betting on the former. The rest of the market is being asked to decide whether this time is actually different.
Not every Natixis affiliate is fully on board. Bruno Poulin, chief executive of Ossiam, a Natixis Investment Managers subsidiary, has said he remains overweight the US while eyeing opportunities in Japan - a reminder that within a multi-affiliate platform, the Japan-over-US call is a strong conviction, not a house-wide mandate. That internal disagreement is itself informative: the rotation is a judgment about relative value and concentration risk, not a verdict that America has lost.
The allocation shift is a verdict that diversification has become cheap relative to concentration, and that a market which spent a decade punishing Japanese boards for hoarding cash is finally rewarding the ones that stopped. Corporate internal reserves in Japan sit at a record 446.5 trillion yen, according to Ministry of Finance data - a pool of capital that governance reform is slowly converting into shareholder returns, and the raw material for the next leg of the rally if boards keep converting it.
"These factors are compounded by the transformation of corporate governance supported by the regulator and the Tokyo Stock Exchange. The implementation of this structural reform - which began a few years ago and is now yielding results - is leading to an increase in share buybacks and higher dividend payouts, while also supporting efforts to improve RoE."
- Mabrouk Chetouane, Head of Global Market Strategy, and Romain Aumond, Senior Macroeconomist and Quantitative Strategist, Natixis Investment Managers, August 2026
"Japan has emerged from its period of hardship, and its resilience - along with its capacity to innovate and invest - will enable its companies and their stock prices to grow within a healthy framework."
- Natixis Investment Managers market strategy team, August 2026
Data as of September 3, 2026.
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