U.S. technology stocks have rebounded, but a warning said it is too early to invest hastily in shares tied to AI data centres.

On Oct. 19, CNBC cited Jim Cramer (짐 크레이머) as saying that even if recently plunging AI beneficiaries rebound, technical and fundamental burdens remain, making it hard to be optimistic about further gains.

Cramer said, "Even if there is a rebound today, it is too early to decide the risk is gone and that it is safe to invest again." He said he is positive about the long-term flow of AI investment, but stressed that four conditions must be met for AI data centre-related shares to keep rising.

The first is an improvement in technical indicators. Cramer said the VanEck Semiconductor ETF and Roundhill Memory ETF appear to show a double-top pattern, a bearish signal. He added that a head-and-shoulders pattern, which can be read more negatively, is also being seen in some names.

He said, "To the eye of a skilled chart analyst, these names look like they have not found a bottom." He also stressed that the Nasdaq Composite and the Nasdaq 100 must regain the 50-day moving average, which is used to judge technical trends.

After last Friday's sharp drop, the Nasdaq Composite and the Nasdaq 100 fell below their 50-day moving averages. On Monday, buying in tech shares lifted the Nasdaq Composite about 1.1 percent and the S&P 500 about 0.5 percent, but the Dow Jones Industrial Average was little changed. The Volatility Index (VIX), known as Wall Street's fear gauge, rose above 22 for the first time in four months.

The second is big tech earnings. Cramer said investors need to check whether large technology companies are willing to keep investing in AI and whether increased spending is translating into actual results. SpaceX and Meta Platforms are set to report results this week, followed next week by Alphabet and Microsoft, and Amazon. He said a key yardstick is whether growth in the public cloud business continues.

The third is the U.S. midterm elections scheduled for Nov. 3. Cramer said political opposition to data centre construction has weighed on the industry, and he forecast that some uncertainty could ease after the election. There could be short-term selling depending on the outcome, but reduced political uncertainty could help AI-related shares build a bottom, he said.

The fourth is an initial public offering by Anthropic. Media reports said the listing could take place as early as November. Cramer said, "At the final stage of investment spending, you need to confirm whether this business is an investment that can generate sustainable profits," adding that Anthropic's IPO could be an opportunity to judge that. He also cautioned that money could be pulled from other AI names as funds crowd into a large IPO.

Cramer said investors should not invest aggressively in AI data centre-related shares until the four conditions are met: improved charts, confirmation of big tech earnings, the end of the midterm elections and an Anthropic listing. He said whether the recent rebound becomes a trend reversal will depend on upcoming earnings, political uncertainty and the flow of investment funds.