Artificial intelligence infrastructure emerged as the strongest investment theme of the first half of 2026, powering dramatic gains in technology-related stocks while traditional safe-haven assets such as gold and cryptocurrencies lost momentum despite global geopolitical tensions.
The first six months of the year were marked by conflicts in the Middle East, political uncertainty and sharp swings in oil prices. Even so, several major stock markets reached record highs as investors focused on companies supplying the hardware needed to support the expanding AI industry.
According to Dan Coatsworth, head of markets at AJ Bell, businesses linked to the rapid build-out of AI data centres delivered some of the strongest returns, while Bitcoin and gold disappointed investors.
Memory chip manufacturers stood out as the biggest winners. SanDisk led gains in the United States after its shares climbed more than 850% during the first half of the year. Western Digital, Micron Technology and Seagate Technology also recorded gains of more than 200%, driven by surging demand for high-speed memory and storage products used in AI systems.
Technology giants and cloud providers have continued investing heavily in new data centres, creating strong demand for advanced memory chips and storage devices. Other AI-related companies also posted strong performances, with Intel, Dell Technologies, Advanced Micro Devices (AMD) and Applied Materials rising between 150% and 280% since the beginning of the year.
The rally extended beyond the United States. Asian semiconductor manufacturers supported strong performances in regional markets, helping South Korea’s KOSPI index double in value while Japan’s Nikkei 225 advanced about 40%. The MSCI Emerging Markets Index gained around 27% during the period.
European markets posted more moderate gains. Britain’s FTSE 100 rose 7%, France’s CAC 40 added 5%, and Germany’s DAX increased 2%. In contrast, the MSCI India Index fell 5%, while Hong Kong’s Hang Seng Index declined 6%.
Some of the technology sector’s former market leaders failed to keep pace. Shares of Meta Platforms and Microsoft fell 14% and 24%, respectively, as investors became more cautious about the heavy spending required to expand AI capabilities. Analysts noted that concerns over rising capital expenditure reduced investor enthusiasm for the companies despite their continued commitment to artificial intelligence.
Assets traditionally viewed as safe havens also struggled. Gold retreated about 28% from its January record high despite ongoing geopolitical tensions, with higher bond yields and interest rates reducing its appeal. Bitcoin also declined 28% during the first half of the year as investor money shifted toward AI-related equities.
In Britain, takeover activity provided support for several blue-chip companies, including Glencore, Schroders and Segro, highlighting continued investor interest in UK-listed businesses. Meanwhile, housebuilders such as Persimmon faced pressure from a weak property market, while defence stocks including BAE Systems, Rheinmetall and Palantir lost momentum after strong gains last year as investors turned their attention to the AI sector.
