Investing.com -- Dolby Laboratories (NYSE:DLB) surged in Friday trading after S&P Dow Jones Indices said it was adding the stock to its MidCap 400 index.
Dolby shares rose 10% as of midday. They are up 20% so far this year.
The audio technology company is replacing STAAR Surgical Company (NASDAQ:STAA), S&P said. Staar's stock was up 3.8%.
At the same time, Staar Surgical will replace Urstadt Biddle Properties (NYSE:UBA) in the S&P SmallCap 600 index, all effective prior to the opening of trading on Aug. 22.
S&P said Regency Centers (NASDAQ:REG) will acquire Urstadt Biddle Properties in a transaction expected to close soon. "Staar Surgical is more representative of the small-cap market space," the index company said.