Dolby stock rises on upcoming move to S&P MidCap 400

Shares of Dolby Laboratories Inc.
DLB,
+0.96%
were up 4.8% after hours on Thursday after S&P Dow Jones Indices said the audio-tech company would replace Staar Surgical Co.
STAA,
+0.17%
in the S&P MidCap 400. Staar Surgical will replace Urstadt Biddle Properties Inc.
UBA,
-1.81%
in the S&P SmallCap 600. The moves take hold before the opening of trading on Aug. 22. “S&P 500 constituent Regency Centers Corp.
REG,
-1.80%
will acquire Urstadt Biddle Properties in a transaction expected to close soon pending final closing conditions. Staar Surgical is more representative of the small-cap market space,” S&P Dow Jones Indices said in a statement.