Dow, S&P 500 and Nasdaq close at record highs on US-Iran deal hopes

S&P 500 and Nasdaq hit record closing highs as US and Iran agree to extend ceasefire

S&P 500 and Nasdaq closed at record highs on May 28 (+0.58% and +0.91%) driven by a US-Iran 60-day ceasefire extension draft and Snowflake surging 36% on a $6B AWS AI deal. For tech leaders, the Snowflake-AWS deal signals that multi-year, billion-dollar AI infrastructure commitments are becoming standard procurement — budget cycles and vendor lock-in timelines are shifting accordingly.