The major averages finished a broadly weaker Monday off their session lows, as late buying interest in technology stocks helped the S&P 500 (-0.3%) and Nasdaq Composite (-0.1%) recover some of their earlier losses. The DJIA (-0.7%) underperformed as rising oil prices and renewed hostilities between the U.S. and Iran weighed on sentiment throughout the session.

Crude oil was a central influence on today's action, settling $2.45 higher (+2.9%) at $85.83 per barrel and recovering a large portion of last week's decline. The move followed the latest hostilities between the U.S. and Iran, while Axios reported during the afternoon that President Trump is considering limited strikes aimed at preventing Iran from reconstituting its capabilities to attack ships in the Strait of Hormuz. The energy sector (+2.1%) was the clear beneficiary, finishing comfortably atop the sector standings.

Most of the market moved in the opposite direction, however, with the Russell 2000 (-0.5%) and S&P Mid Cap 400 (-0.5%) also ending lower.

Technology stocks provided an important source of support, particularly late in the session. The information technology sector (+0.3%) moved into positive territory as semiconductor stocks attracted buying interest shortly before the close, helping pull the major averages off their session lows. The PHLX Semiconductor Index (+0.6%) finished modestly higher and ended August with a 2.0% gain despite considerable volatility throughout the month. NVIDIA (NVDA 220.50, +2.95, +1.36%) was among today's semiconductor standouts after last week's earnings-driven surge.

Elsewhere in the technology sector, CrowdStrike (CRWD 231.00, +12.60, +5.77%) extended its own post-earnings advance to finish as the top-performing S&P 500 component.

Mega-cap performance was less encouraging overall, leaving the Vanguard Mega Cap Growth ETF down 0.2% as most of the Magnificent Seven finished lower. The communication services sector (-1.6%) was among the weakest groups as Alphabet (GOOG 335.41, -7.47, -2.18%) lagged, while Amazon (AMZN 259.77, -6.66, -2.50%) pressured the consumer discretionary sector (-0.7%) after The Wall Street Journal reported that the FTC plans to file a lawsuit against the company. Tesla (TSLA 368.01, +19.26, +5.52%) bucked the broader mega-cap weakness, rallying sharply and climbing back above its 50-day moving average (359.81) amid enthusiasm surrounding autonomous driving and energy-storage developments. Elon Musk's comments outlining an aggressive goal of reaching 100 GW of annual solar production also contributed to the positive sentiment surrounding the stock.

Selling pressure also remained pronounced in several other areas. The utilities (-1.2%) and industrials (-1.2%) sectors finished with sizable losses. Edison (EIX 53.96, -16.21, -23.10%) and PG&E (PCG 13.28, -3.32, -20.00%) continued to weigh heavily on the utilities sector following developments surrounding California wildfire legislation, while weakness across military contractors pressured the industrials sector. Howmet Aerospace (HWM 244.91, -19.94, -7.53%) was a notable laggard after Elon Musk said in-house SpaceX (SPCX 143.75, +2.25, +1.59%) casting of natural-gas turbine blades and vanes could accelerate turbine deployment by up to 18 months.

In other corporate news, Aon (AON 321.34, -34.06, -9.58%) fell sharply after agreeing to acquire USI Insurance Services for $17.0 billion in cash.

Ultimately, Monday's session featured broad underlying weakness as the renewed rise in crude oil prices and U.S.-Iran tensions weighed on sentiment. The energy sector was the clear exception, while late strength in semiconductors and other technology stocks helped the major averages recover from their lows and limited the losses at the index level. Despite ending the final trading day of August on a lower note, the major averages still secured solid gains for the month.

U.S. Treasuries ended August with losses in most tenors, producing fresh 2026 highs in yields on 3-year, 5-year, 7-year, and 10-year notes. The 2- year note yield finished unchanged at 4.35% (+6 basis points in August), and the 10-year note yield settled up four basis points to 4.76% (+1 basis point in August). 

There was no economic data of note. 

• Russell 2000: +19.1% YTD
• S&P Mid Cap 400: +13.8% YTD
• Nasdaq Composite: +13.5% YTD
• S&P 500: +12.3% YTD
• DJIA: +10.7% YTD