Stock Market Update

[BRIEFING.COM] The S&P 500 (+0.7%), Nasdaq Composite (+1.3%), and DJIA (+0.4%) have weathered some choppy action this morning, currently in the upper portion of their respective trading ranges just before midday.

Gains at the index level are underpinned by a solid rebound across mega-cap stocks after a poor showing in the previous week. Alphabet A (GOOGL 351.17, +13.78, +4.08%)is a standout in its first session as a member of the DJIA, while Amazon (AMZN 242.43, +9.74, +4.19%) holds a similar gain after Reuters reported Prime Day spending increased 9.3% year-over-year to $26.4 billion. The Vanguard Mega Cap Growth ETF is up 2.1%.

Meanwhile, swings across semiconductor stocks have been the main driver of this morning's volatility. The PHLX Semiconductor Index is currently up 1.6%, but traded more than 2% lower after reversing a solid opening gain.

Outside of the tech space, action is mixed, with a few noticeable trends at the sector level. The materials sector (-2.4%) lags as construction names give back some of their recent gains that followed a retreat in Treasury yields. Other cyclical sectors trade modestly higher, while more defensive-oriented sectors hold modest losses as mega-cap tech outperforms.