The S&P 500 edged lower on Monday as losses by healthcare companies overshadowed gains in the technology sector, while investors awaited US President Donald Trump's meeting with Chinese President Xi Jinping at the G20 summit this week.
The Nasdaq slipped but tariff-sensitive industrials, headed up by Boeing Co, led the blue-chip Dow Jones Industrial Average to a nominal advance.
While the bellwether S&P 500 ended the session in the red, it remained within a hair's breadth of its all-time closing high reached last Thursday as markets reacted to a dovish statement from the US Federal Reserve.
Market players hope Trump and Xi will de-escalate the trade war that has been blamed for a global economic slowdown.
"Today's very quiet," said Bruce Monrad, chairman and trustee at Northeast Investors Trust in Boston. "People are digesting the Fed and looking forward to possible outcomes of the G20 and how that could in turn affect the Fed going forward."
A Fed rate cut in July "may be locked and loaded but could be somewhat contingent on what happens at the G20," Monrad added.
The Dow Jones Industrial Average rose 8.41 points, or 0.03%, to 26,727.54, the S&P 500 lost 5.11 points, or 0.17%, to 2,945.35 and the Nasdaq Composite dropped 26.01 points, or 0.32%, to 8,005.70.
Six of the 11 major sectors in the S&P 500 lost ground, with the biggest percentage drop for energy stocks as crude prices fell.
In the latest trade-related squabble, FedEx Corp apologized for mistakenly returning a Huawei phone to its sender, after misrouting packages from the Chinese tech firm last month. The move provoked the ire of Chinese authorities and raised the prospect of FedEx being added to China's "unreliable entities" list. The package delivery firm's shares slid by 2.7%.
Caesars Entertainment Corp jumped 14.5% on news that rival Eldorado Resorts Inc had agreed to buy the casino operator for $8.5 billion. Eldorado dropped 10.6%.
United Technologies Corp advanced 1.1% after Cowen & Co upgraded it to "outperform" from "market perform."
Celgene Corp slipped 5.5% after Bristol-Myers Squibb Co announced that its planned $74 billion deal to buy the drugmaker was expected to close at the end of 2019 or beginning 2020, later than expected. Bristol-Myers fell 7.4%.
Declining issues outnumbered advancing ones on the NYSE by a 1.44-to-1 ratio; on Nasdaq, a 2.27-to-1 ratio favoured decliners.
The S&P 500 posted 35 new 52-week highs and 5 new lows; the Nasdaq Composite recorded 42 new highs and 82 new lows. Volume on US exchanges was 6.31 billion shares, compared to the 7.05 billion average over the last 20 trading days.