Shares of technology companies rose as traders rotated into the largest and fastest growing companies on the S&P 500. Strategists warned the surprisingly small number of mega-cap companies leading the stock market this year could be a warning signal.

"This is becoming a narrower and narrower market, which, all things considered, is not as healthy as a broader rally," said J.D. Joyce, president of financial advisory Joyce Wealth Management.

If the S&P 500 were adjusted so that it was not weighted by market capitalization, it would be in negative territory for the year to date, strategists observed.

"I think the market is dangerous -- only mega-cap tech is holding it up," said Lorenzo Di Mattia, manager of hedge fund Sibilla Global Fund.

"The S&P Equal weight looks much worse than the S&P and the transportation and Russell 2000 indexes even worse."

Alphabet's Google has used unfair tactics to hobble Microsoft's Bing search engine, Microsoft Chief Executive Satya Nadella alleged on the witness stand Monday in the landmark U.S. antitrust case against Google.

Tesla shares fell after the electric-car maker said sales momentum slowed during the third quarter as the automaker took production offline for factory upgrades.


Write to Rob Curran at rob.curran@dowjones.com

(END) Dow Jones Newswires

10-02-23 1749ET