The S&P 500 rallied on Thursday as semiconductor stocks rebounded and oil prices eased, but Polymarket traders are betting the benchmark index will open lower on Friday.

The S&P 500 gained 0.81% to close at 7,543.64.

However, the July 10 Polymarket contract implied just a 20% probability that the index would open higher on Friday, reflecting expectations of a weaker start after the latest rally.

Why That Number Matters Thursday's rally underscored how quickly sentiment can shift as investors weighed easing oil prices against persistent geopolitical uncertainty.

Semiconductor stocks once again led the market higher, reinforcing the view that artificial intelligence remains the primary driver of this year's bull market even as investors rotate between sectors.