Something unusual is happening on the Tokyo Stock Exchange. Average daily trading volume on its prime market has almost doubled in the past year, topping ¥10 trillion—about $63 billion—for the first time ever. Driving the surge is an old character with a new obsession: 'Mrs Watanabe,' the industry nickname for Japan's individual retail investors, who have piled into stocks tied to artificial intelligence and semiconductors. Names like Furukawa Electric, Fujikura, Nitto Boseki, and Mitsui E&S—companies that supply cables, materials, and equipment to the AI build-out—have become retail favorites, the 'picks and shovels' of the boom.
Retail's share of trading on the TSE reached 25% over the past year, the highest level since the early days of 'Abenomics,' the stimulus program launched by former Prime Minister Shinzo Abe more than a decade ago. But analysts at Jefferies argue the official number understates what's really going on. The TSE's data doesn't capture some margin trading or activity on 'off-exchange' venues—proprietary trading systems run by online brokers like Rakuten, SBI, and Monex. Two of those venues, Japannext and JAX, now dominate the off-exchange world. JAX's chief executive Takeya Kamei says roughly half of his platform's volume comes from retail; most of the rest is supplied by high-frequency market makers who keep prices liquid.
Here's the catch. As more individual investors route orders through these less-visible venues, the public market becomes harder to read. The official price on the TSE may not reflect the full weight of demand moving through hidden channels. In calm markets that's a minor accounting problem. In a momentum-driven AI rally, where a single earnings miss can crater a stock, it becomes a transparency problem—analysts and ordinary watchers can't tell whether a rising share price reflects broad enthusiasm or thin visible liquidity being pushed around by unseen flow.
Market professionals say the fingerprints of retail are everywhere this earnings season. Jeff Hutchins, head of equity trading in Japan at Jefferies, notes that stocks have been punished or rewarded for even minor deviations from analyst expectations—a hallmark of momentum traders rather than long-term institutions. Oki Matsumoto, founder of Monex, puts it more bluntly: index-tracking exchange-traded funds that used to dominate retail activity are losing ground to direct bets on individual AI-related stocks. Investors aren't just buying the market anymore; they're picking winners.
The Japanese government, perhaps surprisingly, is cheering this on. For decades, Japanese households parked their savings in bank accounts paying near-zero interest. Now, with interest rates finally rising, policymakers want savers to shift cash into investments that might fund retirement—and a vibrant retail market is part of that plan. Off-exchange venues, regulators argue, also introduce useful competition to the TSE and lower trading costs.
Still, two facts complicate the cheerful story. First, foreign institutions and Japanese corporations remain the biggest buyers of Japanese equities; despite the noise from retail, households on net are actually using rising prices to *trim* their long-term holdings, not expand them. Second, the last time Japan saw retail enthusiasm at anything like today's levels was the 1980s asset bubble, whose collapse haunted the economy for thirty years. The current rally has powerful structural support—genuine AI demand, rising rates, government backing—but it's running through a market structure that has quietly changed shape underneath investors' feet. Whether Tokyo can absorb a retail boom without sacrificing trustworthy price discovery is now the question regulators, brokers, and Mrs Watanabe herself will spend the next year answering.
Source: https://www.ft.com/content/ai-fever-off-exchange-boom-japanese-retail-traders
Japan's amateur investors just doubled their trading in a year, piling into AI stocks—but increasingly they're trading in the shadows, on venues regulators can barely see.
Average daily trading on the Tokyo Stock Exchange's prime market has almost doubled in 12 months, topping ¥10 trillion ($63 billion) per day for the first time. The surge is driven by ordinary Japanese investors—nicknamed 'Mrs Watanabe'—chasing AI and chip stocks like Furukawa Electric, Fujikura, and Nitto Boseki.
But here's the twist: a growing slice of that trading isn't happening on the TSE at all. Retail investors are increasingly routing orders through 'off-exchange' venues—proprietary trading systems run by brokers like Rakuten, SBI, and Monex—where prices and volumes are harder to track. Retail's share of TSE volume hit 25% last year; analysts say the real number is even higher once these hidden venues are counted.
Two things are happening at once: a story-driven bull market AND a structural shift in *where* trading happens. To grasp it, try these:
If you're thinking about finance, economics, or just understanding the news, Japan is the world's clearest case study right now of how the AI boom reshapes a whole society's relationship with money. Japanese households have hoarded cash for 30 years because interest rates were near zero; now, with rates finally rising and AI mania providing irresistible stories, ordinary people are becoming traders. That same shift—retail investors mattering more than ever—is happening on Robinhood in the US and Zerodha in India too.
The last time retail enthusiasm in Japan looked anything like this was the 1980s bubble that ended in a 30-year hangover. This time the government is cheering it on—but if AI stocks roll over, the same off-exchange venues that made trading easier could make the unwind faster and harder to monitor. Watch two things: whether Japanese regulators demand more transparency from broker-run platforms, and whether foreign institutions—still the biggest sellers in Tokyo—keep dumping shares into retail's buying.