Close: Stocks finish mixed as Nasdaq proxy falls, Dow edges higher

U.S. stocks ended Monday, Oct. 12, 2026, mixed, with the Dow proxy rising as Nasdaq and small-cap proxies retreated. SPY, which tracks the S&P 500, slipped 0.06% to $778.10, while Nasdaq 100 tracker QQQ fell 0.70% to $746.04. Dow tracker DIA gained 0.35% to $517.91, and Russell 2000 tracker IWM lost 0.37% to $277.90.

Large-company shares diverged: Apple rose 1.29% to $340.97 and Microsoft gained 1.14% to $541.15, while Nvidia declined 1.29% to $226.32. Exxon Mobil advanced 1.90% to $172.15, finishing near its session high of $172.55. JPMorgan Chase added 0.39% to $334.30.

Losses were sharper among several mid- and small-cap names. Mid-cap IonQ dropped 9.07% to $36.27, while small-cap Aehr Test Systems fell 7.63% to $78.18. Plug Power lost 3.57% to $1.62, and Intuitive Machines declined 2.50% to $12.86.

Micro-cap shares also came under pressure, with ClearSign Technologies sliding 7.79% to $2.96 and Duos Technologies falling 6.39% to $6.74. Both finished near their session lows of $2.92 and $6.6513, respectively.

Geopolitical developments featured prominently in the headlines: Reuters reported fresh missile and drone fire against Saudi Arabia following major airport attacks, alongside airline cancellations and the continued closure of Riyadh's airport this week. Reuters also reported that U.S. officials hoped a diesel deal with Russia could help advance peace talks, while lawmakers from both parties criticized the agreement. In corporate coverage, CNBC highlighted a double upgrade of Salesforce.

The next session's watch points include further developments in Saudi airport disruptions and the U.S.-Russia diesel agreement. On the tape, attention turns to whether the Dow proxy's relative strength persists and whether Nasdaq and smaller-company shares stabilize.