Tokyo, September 7 — Advantest Corporation (TYO:6857) emerged as the primary engine of the Nikkei 225's morning rally on Monday, contributing over a quarter of the index's gains before giving back some ground in the afternoon session. The semiconductor test equipment maker's shares climbed as much as 5.32% to ¥34,850 before retreating to ¥34,310 by 2:17 p.m. Japan Standard Time, still 3.69% above Friday's close.
The stock's performance underscores the market's continued appetite for AI-related chip names, even as the broader market showed signs of narrowing breadth. At the midday break, the Nikkei had advanced 1,439.17 points, with Advantest alone contributing 386.17 points, or 26.8% of that rise, according to data from Kabutan. SoftBank Group and Tokyo Electron were the next largest contributors, together with Advantest accounting for roughly 71% of the index's advance. Yet beneath the surface, declining stocks outnumbered advancers on the Tokyo Prime Market, 826 to 681, highlighting a market that is increasingly reliant on a handful of heavyweight names.
The rally in Advantest shares has solid company-specific support. In July, the company raised its fiscal 2026 sales forecast to ¥1.714 trillion, a 51.9% increase from the previous year, and lifted its operating income projection to ¥846 billion, up 69.5%. The revised outlook implies basic earnings per share of ¥911.64, a figure that at Monday's afternoon price translates to a price-to-earnings multiple of 37.6 times.
That valuation premium reflects the market's confidence that the current shortage of testers will continue to convert into earnings growth. The latest quarter provided ample evidence for the bulls: sales surged 39.3% to ¥367.5 billion, while operating income jumped 53.3% to ¥190.0 billion, pushing the operating margin to a remarkable 51.7%. Test systems accounted for ¥333.6 billion, or 90.8% of group sales, according to the company's financial review.
During the July 29 earnings call, Group CEO Douglas Lefever described demand as broad-based across GPUs, custom ASICs, and CPUs. The company's official Q&A summary attributes the revenue boost to longer test times and additional test steps, driven largely by the complexity of 3D packaging technologies. Advantest estimates it held a 66% share of the system-on-chip tester market in calendar 2025, with management seeing a path to exceed 70%. Memory testing remains a weak spot, with the company cautioning that its share in that segment may decline this year during product transitions.
However, the full-year forecast implies a second-half operating margin of 47.3%, below the first quarter's stellar 51.7%. Management has already flagged the reasons: higher memory-component prices are expected to pressure costs, and the first quarter benefited from an inventory-obsolescence reversal that is unlikely to recur. These factors set up a critical test for the October earnings report, which will be scrutinized for second-half margin guidance and any update on memory-tester market share.
The stakes are high. Another upward revision would make the current valuation easier to justify, but a margin slide toward or below 47.3% could leave Monday's buyers paying a steep price for growth that is already baked into forecasts. Analysts remain divided on the stock's prospects, with a 21-analyst survey from S&P Global, published by StockAnalysis, showing an average price target of ¥41,362, but with a wide range from ¥23,000 to ¥55,000.
Monday's index arithmetic cannot resolve that disagreement. The next margin print will provide a clearer signal on whether Advantest's premium valuation is warranted. For now, the market's enthusiasm for AI-driven semiconductor demand remains undiminished, but the narrowing breadth of the rally serves as a reminder of the concentration risk that has come to characterize the current bull run.
