U.S. major stock indexes closed mixed on Monday, with investors assessing Treasury yields and the euro exchange rate while awaiting the upcoming earnings season. Later this week, the Federal Reserve will release the minutes from its September policy meeting, though the overall calendar of market events remains relatively light.

The Dow Jones Industrial Average slipped 0.13%, the S&P 500 gained 0.08%, and the Nasdaq Composite rose 0.13%. Among individual movers, PTC Inc. surged 35.91%, Western Digital climbed 5.78%, and MercadoLibre advanced 5.39%, while C.H. Robinson Worldwide dropped 10.12%, FER fell 3.08%, and Align Technology declined 2.95%.

Within the so-called "Magnificent Seven" group, Microsoft (MSFT) rose 1.53%, NVIDIA (NVDA) gained 0.57%, Meta Platforms added 0.45%, Google edged up 0.08%, Amazon ticked up 0.04%, Apple fell 0.51%, and Tesla slid 0.81%.

Monday's corporate earnings and economic calendar was sparse, with the key releases being the S&P Global and the Institute for Supply Management (ISM) purchasing managers' index reports. Ahead of the full launch of the third-quarter earnings season in mid-October, the market will be watching a handful of corporate reports later this week from Levi Strauss, Applied Digital, PepsiCo, and Delta Air Lines.

Despite recent violent swings in the bond market and the ongoing war in the Middle East, equities have remained resilient. The benchmark 10-year Treasury yield rose nearly 3 basis points to 5.303%, while the 30-year Treasury yield also climbed about 3 basis points to 5.663%. Both yields have surged to multi-year highs in recent weeks as markets worry that inflation will force the Federal Reserve to keep interest rates elevated for longer. The Fed raised its overnight policy rate by a quarter percentage point last month. After the release of the September meeting minutes on Wednesday, investors will gain deeper insight into the discussions behind that rate decision.

Meanwhile, oil prices diverged on Monday. Brent crude rose 0.3% to $102.67 a barrel, holding firmly above the $100 mark. Some strategists have already sounded warning signals, though other analysts believe there is still room for further upside. U.S. West Texas Intermediate crude fell about 0.6% to $88.92 a barrel.

Investors on Monday will also be watching the ISM services sector report. In the week just past, the dominant market theme was soaring Treasury yields; an unexpectedly weak nonfarm payrolls report somewhat eased concerns that the Federal Reserve would raise rates again this month. After a week of pressure from rising bond yields, the jobs data offered the market a brief respite.

Citi strategist Beata Manthey wrote in a research note: "Despite growing headwinds (such as geopolitical conflict and a high interest rate environment), global equities are up about 12% year-to-date and are just a stone's throw from record highs. Does this relatively calm situation mean equity fundamentals can withstand persistent macroeconomic shocks, or will stocks eventually pull back to more realistically reflect the current risk environment? While uncertainty remains high, we currently lean toward the view that the market is resilient."

DBS CIO: AI Tech Stocks Far From Bubble Territory

DBS Group Chief Investment Officer Hou Wey Fook said that NVIDIA (NVDA)'s price-to-earnings ratio, combined with an expected 70% earnings growth rate next year, shows that artificial intelligence (AI)-driven tech stocks are far from entering bubble territory. Data shows that NVIDIA currently trades at about 17 times its expected earnings over the next 12 months. Hou compared this valuation with Cisco (CSCO)'s 100-times valuation before the dot-com bubble burst. "If the benchmark company of the AI trade is valued at only a teens multiple, how can you call it a bubble?" he said in an interview, adding that semiconductors and the AI trade still have "tailwinds."

Still, Hou advocates a "barbell" strategy to "control the overall volatility of the portfolio": combining growth-oriented tech stocks with investment-grade fixed income products to achieve stable returns, while using hedge funds and gold as intermediate risk-diversification tools. In terms of market performance, NVIDIA's stock hit a record intraday high last Friday, coming within striking distance of becoming the first listed company in the world to top a $6 trillion market capitalization. NVIDIA is up about 25% year-to-date and currently has a market value of roughly $5.6 trillion.