Renesas Electronics Rises Over 7%, SoftBank Rises Over 4%, Can Japanese Chip Stocks Replicate South Korean Stocks’ Soaring Rally?

First is the spillover effect of AI computing power demand. As the Philadelphia Semiconductor Index hits all-time highs, market sentiment has rapidly mirrored into the Asia-Pacific supply chain. Overseas investors have net-bought 5.69 trillion yen in Japanese equities this year, serving as a vital source of incremental capital driving the Nikkei higher.

South Korean memory giants SK Hynix and Samsung Electronics continue to expand production, while Japanese firms like Tokyo Electron, Advantest, and Lasertec—which provide upstream manufacturing equipment—hold near-monopoly positions in their respective niches. Memory expansion is constrained by equipment supply bottlenecks, which provides structural support for the mid-to-long-term earnings of Japanese equipment stocks.

Secondly, the Japanese government is aggressively funding the chip industry, with appropriations for semiconductors and AI in FY2026 increasing to approximately 1.23 trillion yen, nearly quadruple the previous budget. Over the longer term, a $65 billion initiative is expected to leverage roughly 160 trillion yen in economic impact by 2030.

Furthermore, geopolitical conflicts have seen a phased de-escalation. On May 12, the U.S. signaled a cooling of tensions regarding tariffs, causing trade uncertainty to recede at the margin. Signs of dialogue have also emerged in the Middle East; as oil prices retreated after peaking, market concerns over a full-scale escalation of the conflict have eased.

For Japanese chip stocks individually, the transmission logic for benefiting from AI infrastructure is clear, and there is indeed significant upside potential. However, if asked whether they can replicate the performance of South Korean stocks, the likelihood is low due to their position in the industry chain and weighting structure.

The rally in South Korea's KOSPI index is highly concentrated in two stocks, Samsung Electronics and SK Hynix, which together account for approximately 45% of the index's weight. Both are global leaders in HBM and general-purpose memory chips.

When AI demand triggers a memory chip supercycle, the leverage these two heavyweights exert on the index is immediate. Goldman Sachs raised its KOSPI target to 9,000 points, while JPMorgan sees it reaching 10,000 points; the core logic for both is the memory chip supercycle driven by AI infrastructure.

In contrast, Japan presents a different landscape. Its advantages in the semiconductor sector are concentrated in upstream materials and equipment. Tokyo Electron is a leader in etching and coat/develop equipment, Shin-Etsu Chemical is the world's largest supplier of silicon wafers, and Advantest holds a leading market share in testing equipment.

The performance of these companies is highly correlated with global semiconductor capital expenditure, yet they do not possess pricing power for end products. Their profit advantages are significantly weaker than those of SK Hynix, which directly captures the HBM premium.

At the index level, the weighting of semiconductor-related stocks in the Nikkei 225 is far less concentrated than in South Korea, and they are distributed across different segments of the industry chain. Consequently, the efficiency with which the rally is transmitted to the broader market is significantly limited. During the historic single-day surge of over 5.5% in the Nikkei 225 on May 7, the broader TOPIX rose by only about 3%.

Japanese investors may witness a strong rally among several chip leaders rather than a semiconductor-driven index-wide bull market.

Although it is difficult to translate into an exponential rally, the position of Japanese chip stocks within the AI value chain still provides opportunities.

The growth certainty of the global semiconductor market is high. Morgan Stanley predicts that global investment in AI data centers will reach approximately $2.8 trillion between 2026 and 2028, with an annual growth rate of about 33%.

Japanese companies hold leading positions in upstream materials and equipment segments. Regardless of which chipmaker wins in the end market, capacity expansion always requires equipment and materials, allowing the Japanese supply chain to benefit steadily from every round of capital expenditure.

Japan has extremely high barriers to entry in critical semiconductor materials. Tokyo Electron holds a market share of over 90% in niche segments such as coater-developers, while the ABF produced by Ajinomoto accounts for more than 95% of the global market for high-performance chip packaging materials.

The fundamentals of local companies are also improving. NAND flash manufacturer Kioxia's market capitalization has jumped from 43rd to 5th in Japan, overtaking Hitachi and Sony, with its fiscal 2026 operating profit expected to reach 4 trillion yen. Renesas Electronics recently completed the acquisition of Irida Labs, accelerating its expansion into edge AI vision software.

The bullish thesis holds, but sustained strength still faces multiple constraints.

First is the divergence between macroeconomics and the market. The Bank of Japan has lowered its FY2026 GDP growth forecast to 0.5% while raising the core CPI forecast to 2.8%; despite domestic demand being clearly under pressure, the Nikkei Index hit a new high during the same period.

The current rally is primarily driven by the global semiconductor cycle, and the disconnect between chip stock earnings and the domestic economy can be maintained for the time being.

Once the Yen interest rate hike materializes and currency appreciation erodes export profits, this disconnect is likely to narrow, leaving high valuations to face dual pressure from both earnings and valuation compression. While internal disagreement within the central bank regarding the timing of rate hikes persists, the probability of another move in June or July remains significant.

Weak domestic demand is also constraining market breadth. The April Services PMI fell to 51, while input costs rose to a one-year high, meaning consumption can hardly provide additional support.

Structural divergence is also flashing a warning sign, as the index is almost entirely driven by a few heavyweights like SoftBank and Advantest, while most individual stocks have failed to follow suit.

Japanese chip stocks are unlikely to replicate the single-day surges seen in South Korean equities, as fundamental differences exist in the market structures and industry concentrations of the two countries. However, Japan is undergoing a deeper and more sustainable transformation, shifting from an automotive-driven economy to one powered by chips, and transitioning from end-product manufacturing toward 'hidden champions' in equipment and materials.

For investors, the opportunity in Japanese chip stocks lies not in chasing the explosive growth rates seen in Korea, but in recognizing the bottleneck value within the upstream supply chain; this represents a 'slow bull' market rather than a speculative frenzy.

This content was translated using AI and reviewed for clarity. It is for informational purposes only.