US Stocks Mixed: Reddit Surges on S&P 500 Inclusion as Applied Materials Dips

Key Facts

In a move reflecting structural shifts in major market indices, Reddit shares rallied as the social media platform prepares to join the S&P 500 index. This inclusion is a significant milestone for the company, as it typically drives institutional buying from index-tracking funds. Conversely, Applied Materials shares dipped after its earnings report failed to impress investors or meet high market expectations.

Looking at peer and sector performance per market data, Reddit (RDDT) closed at $158.12 on August 13, 2026, after reaching a day high of $159.29. In the semiconductor equipment space, Applied Materials (AMAT) ended the same session at $534.54, while SNDK stood at $1528.11 at the close of August 13, 2026. These movements highlight a divergence in risk appetite between index rebalancing optimism and the evaluation of tech sector earnings.

Traders should watch support levels for AMAT after it hit a day low of $531.79 on August 13, 2026. With no major upcoming catalysts in the economic calendar directly impacting these instruments in the next few days, focus remains on institutional liquidity flows into Reddit ahead of its official index entry and the market's continued digestion of tech hardware earnings.