US markets swung after President Donald Trump claimed US-Iran "productive" talks. At 7:10 AM ET, S&P 500 surged 240 points, adding $2 trillion in market value, according to Kobeissi Letter. Minutes later, Iran denied talks, triggering reversal that saw S&P 500 fall 120 points by 8:00 AM ET, erasing nearly $1 trillion and marking $3 trillion swing in an hour.