20年来首现“过度投资”！美银基金经理调查：AI泡沫已成市场上最大“尾部投资”

Core Insights - Market sentiment is at a delicate crossroads, with rising optimism about economic prospects but increasing concerns about an AI-driven investment bubble and excessive corporate investment, a warning signal not seen in 20 years [1][4] Group 1: Investor Sentiment and Market Positioning - A recent Bank of America survey indicates that fund managers' stock allocation has reached its highest level since February 2025, while cash holdings have dropped to just 3.7%, triggering a "sell signal" [1][14] - Despite the optimistic sentiment, 63% of respondents believe current stock market valuations are too high, reflecting a growing caution among investors [3][6] - 45% of respondents view the "AI bubble" as the biggest tail risk in the market, a significant increase from 33% the previous month [6][9] Group 2: Concerns Over AI and Corporate Investment - 53% of fund managers believe AI stocks are in a bubble, highlighting a stark contrast between market behavior and investor sentiment [6][9] - The report indicates that for the first time since August 2005, a net 20% of fund managers believe there is "excessive investment" by companies, attributed to concerns over the scale and financing of AI-related capital expenditures [9][12] - 43% of investors see broad AI productivity improvements as the most bullish catalyst for 2026, while 26% view a slowdown in AI capital spending as a significant bearish factor [9][20] Group 3: Asset Allocation and Future Outlook - In November, investors significantly changed their asset allocation, increasing holdings in healthcare (net 40% increase), emerging market stocks (net 36% increase), and bank stocks (net 36% increase) [18] - Looking ahead to 2026, 42% of investors expect international stocks to be the best-performing asset class, with 30% anticipating the Japanese yen to perform best among currencies [20] - 45% of investors expect the 10-year U.S. Treasury yield to be in the 4.0%-4.5% range by the end of 2026, while 34% expect gold to trade between $4000 and $4500 per ounce [20]