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By Jiaxing Li

HONG KONG, Feb 13 (Reuters) - Chinese tech stocks reversed their rally on Thursday after reaching multi-year highs, as AI-driven gains slowed amid traders locking in profits and renewed concerns over the country's economic challenges.

The Hang Seng Tech Index .HSTECH closed nearly 1% lower, after rising 4.2% to its highest point since 2022 earlier in the day. The city's benchmark Hang Seng Index .HSI weakened 0.2% to retreat from a four-month high.

Among the biggest decliners, chipmaker SMIC 0981.HK slid 4.1% and rival Hua Hong Semiconductor tumbled 5.2%.

Shares of internet companies pared early gains. Alibaba 9988.HK closed 2.6% higher after briefly touching a three-year high following Chairman Joe Tsai's announcement that the e-commerce giant will partner with Apple AAPL.O on AI for iPhones sold in the China market.

Baidu 9888.HK finished 5.7% higher, well off its intraday peak of 12%, following news that the company would offer its AI chatbot Ernie Bot free of charge from April 1.

Mainland stocks also weakened, with China's blue-chip CSI300 Index .CSI300 and the Shanghai Composite Index .SSEC both slipping by around 0.4% each to retreat from their highest levels so far this year.

"Technology innovation alone cannot resolve China's structural economic imbalance or cyclical deflationary problems," analysts at Morgan Stanley said in a note on Thursday.

"As we go through the policy vacuum period until the March NPC, concerns about the macro slowdown are likely to reduce the broad beta opportunity."

Still, Hong Kong's benchmark index has advanced 8.8% so far this year, making it the best performer among major markets in the region, largely due to DeepSeek-triggered tech rally and China's market rescue measures last month.

Meanwhile, the Hang Seng Tech index has rallied over 60% since the September trough, as it may finally be beginning to slough off years of underperformance, driven by government crackdowns on tech giants and a dour broader mood, said Nick Ferres, chief investment officer at Vantage Point Asset Management in Singapore.

"We don't know if the Alibaba AI model is superior, or if they can monetise the platform, but the stock trades on 10 times earnings, net cash on balance sheet and is buying back shares," Ferres said.

There is a strong case for potential re-rating, especially for Hong Kong-listed Chinese stocks, in which the valuation is much more attractive, Raymond Ma, chief investment officer, Mainland China and Hong Kong at Invesco, said in a note.

Re-rating opportunities would come when the market reassess China's innovative capabilities and corporate earnings growth following the AI breakthrough, he added.

(Reporting by Jiaxing Li in Hong Kong; Editing by Sherry Jacob-Phillips)

((jiaxing.li@tr.com))