On June 1, bullish sentiment swept across Asia-Pacific markets in a synchronized rally. Japan's Nikkei 225 Index surged approximately 3.8%, breaking through the 67,000-point milestone for the first time intraday. SoftBank Group's market capitalization briefly exceeded ¥47 trillion, overtaking Toyota Motor to become Japan's second-largest listed company by market value.

South Korea's KOSPI gained more than 4%, trading above 3,120 points and recording its largest intraday advance in nearly two years. The index now ranks among the world's top three major equity benchmarks in year-to-date performance. Samsung Electronics surged 7.7% to a record high, accounting for nearly one-quarter of the index's daily gain. SK Hynix rose more than 8%, with its share price surpassing ₩280,000.

Taiwan's Weighted Index climbed above 28,000 points during the session, setting a new all-time high and gaining approximately 2.1%. Taiwan Semiconductor Manufacturing Co. (TSMC) advanced 3.6%, while Hon Hai Precision Industry rose 2.8%. U.S. futures also joined the rally, with Nasdaq-100 futures gaining 1.1% and Philadelphia Semiconductor Index futures rising 1.5%.

What Happened?

First, AI Semiconductor Export Data Surprised to the Upside

Last Friday, South Korea's Ministry of Trade, Industry and Energy revised its preliminary May export figures, raising semiconductor export growth from 38% to 43%. Exports of semiconductors to China surged 55%.

On the same day, Japan's Ministry of Finance reported that exports of semiconductor manufacturing equipment jumped 62% year-over-year in May, marking the seventh consecutive month of double-digit growth.

Meanwhile, TSMC released its May revenue figures before Monday's market open, reporting annual growth of 38%, well above market expectations.

Demand driven by artificial intelligence has not peaked. Instead, growth is spreading across broader segments of the semiconductor supply chain, including manufacturing equipment, materials, advanced packaging, and memory products.

SK Hynix's High Bandwidth Memory (HBM) production capacity for the second half of 2026 has already been fully booked. Samsung Electronics is expected to complete Nvidia's HBM3E certification process by mid-June.

Dell recently disclosed an AI server order backlog worth $62 billion, which is translating directly into increased procurement orders for Asian memory and semiconductor equipment suppliers.

Second, Middle East Ceasefire Expectations Pressured Oil Prices

Senior U.S. officials indicated over the weekend that the United States and Iran could sign a preliminary agreement as early as this week, including a phased easing of maritime restrictions.

Brent crude oil fell below $98 per barrel during Asian trading hours, reaching its lowest level in nearly two months.

For the highly energy-import-dependent economies of Japan, South Korea, and Taiwan, lower oil prices directly improve trade balances and corporate earnings expectations.

Third, Foreign Capital Returned Aggressively

Data from the Korea Exchange showed that foreign investors purchased approximately ₩2.15 trillion worth of Korean equities on June 1, marking the largest single-day net inflow in nearly three months. More than 70% of those purchases were concentrated in semiconductor and semiconductor equipment stocks.

Taiwan Stock Exchange data showed foreign investors have purchased more than NT$180 billion worth of Taiwanese equities since May, with an additional net inflow exceeding NT$30 billion on June 1 alone.

In Japan, overseas investors recorded their highest weekly net equity purchases of the year during the final week of May.

Key Variables to Watch Going Forward

Although Asia-Pacific markets delivered an exceptionally strong collective breakout on June 1, several factors will determine whether the rally can continue.

First, the timing and implementation of any Middle East agreement remains the most important external variable. If the preliminary agreement referenced by U.S. officials is signed this week, Brent crude could potentially fall below $95 per barrel, providing a broad valuation boost for Asia-Pacific manufacturing and industrial assets.

However, if negotiations are delayed again, commodity prices that have declined on ceasefire expectations could quickly rebound, creating headwinds for equity markets.

Second, Samsung Electronics' ability to secure Nvidia's HBM3E certification in mid-June will be a critical catalyst for South Korea's stock market. If certification is confirmed, Samsung could win orders for Nvidia's next-generation AI chips, creating additional upside potential for its shares and the broader semiconductor sector.

Third, U.S. inflation and monetary policy remain key global risk factors. The U.S. Consumer Price Index (CPI) for May will be released on June 11, followed by the Federal Reserve's interest-rate decision on June 16–17.

After the strong gains in Asia-Pacific equities driven by AI-related optimism and geopolitical developments, any upside surprise in U.S. inflation could reinforce a hawkish Federal Reserve stance. Such an outcome would place pressure on growth-stock valuations globally, making it difficult for Asia-Pacific technology shares to remain insulated from broader market weakness.