Nasdaq, S&P 500 Rebound Strongly On Signing Of U.S.-Iran Deal

The Nasdaq and S&P 500 reversed a late-session slide Thursday and rallied through the close after the U.S. and Iran signed a deal. The signing removed a source of geopolitical uncertainty that had kept a lid on equities in prior days. The move was broad-based, with technology and energy shares leading the advance.

The agreement was announced mid-morning, and buying interest accelerated into the afternoon. Volume picked up, suggesting institutional participation rather than a short-covering squeeze alone. The Dow also joined the rally, though its gain was more modest.

The deal marks a diplomatic shift after months of tension in the Persian Gulf. Traders had been positioning for a range of outcomes, and the actual signing caught many off guard. The market's reaction reflected relief that a military escalation was avoided, at least for now.

Thursday's session snapped a two-day losing streak for the S&P 500. The index had fallen 1.2% over the prior two sessions as the negotiations dragged on. The Nasdaq, more sensitive to growth expectations, rebounded more sharply.

The next catalyst for broad indices will be the Federal Reserve's rate decision later this month. For now, the geopolitical overhang has receded, and investors are refocusing on earnings and economic data.