U.S. stocks turned mostly negative on Monday, with the S&P 500 and Dow industrials retreating from record highs, after activist investor Carl Icahn said he is "very cautious" on equities.
"It's pretty much Icahn and the benefits of Twitter" that deflated the market, said Art Cashin, director of floor operations at UBS, referring to tweets of Icahn's comments made at a Reuters summit Monday afternoon.
Speaking at the Reuters Global Investment Outlook Summit, Icahn said he could see a 'big drop" in stocks because earnings at many companies are driving more by low borrowing costs rather than strong management.
After clearing 16,000 for the first time, the Dow Jones Industrial Average rose to an intraday record of 16,030.28, before falling below the psychologically important level late in the session. It ended at 15,976.02, its fourth consecutive closing high, up 14.32 points, or 0.1 percent.
Boeing led blue-chip companies on the rise, after the plane maker received more than 250 orders for its revamped 777 jet at an airshow in Dubai.
The S&P 500 also surpassed a psychological hurdle, rising above 1,800 for the first time, before clearing gains to finish down 6.65 points, or 0.4 percent, at 1,791.53. It had set an intraday record of 1,802.37.