The Dow Jones Industrial Average has hit new highs and the S&P 500 index has set records, while U.S. Treasurys continue to push higher. Each asset class competes for investors' monies, so typically stocks rally or bonds rally, but not both together.
Since stocks and bonds typically trade inversely, professional trader Jim Iuorio said Treasurys have advanced on fears the prolonged stock market rally could soon come to an end.
To pro trader Anthony Grisanti, it's foreign investment that's driving bond prices higher.
"My theory is it's the money that's coming in from overseas, with all the liquidity that's happening there. That money has to go somewhere," said Grisanti, founder of GRZ Energy. "If it ain't going into equities, it's going to go into bonds and I think it's coming from them."