The S&P 500 was up 0.3% in midday trading to 2,637.61.
The Dow Jones Industrial Average rose 0.3% to 24,222.30.
The Nasdaq climbed 0.6% to 6,813.46.
The yield on a 10-year Treasury bond went up 1.1% to 2.36%.
The price of gold dropped 1.1% to $1,252.
Edwards Lifesciences Corp. (NYSE: EW) in Irvine was up 4% to $118 and a $25 billion market cap. The heart valve maker said it would buy back $1 billion of its shares, affirmed 2017 guidance, and said it bought a mitral valve repair device maker for up to $250 million.
Biolase Inc. (Nasdaq: BIOL) was up 10% to 44 cents and a $34 million market cap on high volume. The dental laser maker had by midday traded shares at twice its 90-day average.