Japan's Nikkei end lower as AI stocks tumble, geopolitical risks weigh

(Adds details and closing prices) By Rocky Swift TOKYO, Oct 13 (Reuters) — Japan's Nikkei closed lower on Tuesday as a selloff in AI-related stocks gathered pace after weakness in US chip shares, while geopolitical tensions further dampened risk sentiment. The benchmark Nikkei 225 fell 1.82% to close at 67,777.52, losing ground for a fourth consecutive session. The broader Topix rose 0.14% to 4,110.67. Weakness in semiconductor stocks weighed heavily on the Nikkei after the Philadelphia Semiconductor Index fell 1.2% overnight. Japan's inflation picture also remained in focus, with the Bank of Japan (BOJ) reporting wholesale inflation at 6.8% year-on-year in September, while uncertainty over the US Federal Reserve's next policy move and geopolitical risks in the Middle East and Ukraine kept investors cautious. Concerns are mounting about whether massive investments in AI hyperscalers will pay off, said Maki Sawada, an equities strategist at Nomura Securities, while the effects of global hotspots on energy prices are also keeping a lid on optimism. "It's fair to say that today's Japanese stock market is being affected by the downward trend in US semiconductor-related shares," Sawada